Mobile New F350 antenna

[powerscol]

Good morning folks.

First some background information. I currently have an 04 F350 crew cab long bed DRW, with a roof mount Wilson 1000. My radio is a Galaxy DX 95T (export) that was tuned at purchase when it first came out. If I remember correctly the output is north of 150 watts. MY current set up does very well with a constant 7 to 10 mile range on the road. I am retired now and want to have this radio for communication/emergency while exploring our great country again. Family traveled a lot when I was a kid.

Now Ford is constructing their trucks out of aluminum with a steel frame. My new truck will be an F350 super cab long bed SRW. I DO NOT WANT TO DRILL A HOLE IN THE ROOF THIS TIME. Sorry if putting emphasis on this is objectionable, but a lot of folks are telling me to do it with grounding everything (cab and bed at all corners) I will be towing a 5th wheel so bed mount is out, and I don't want a hood mount (tried that before). I don't have room for a headache rack either due to the clearance of the 5th wheel and the cab. The roof hole would be an absolute last resort. A bed stake mount would also interfere with the trailer.

So in searching mounting options I ran across what is called a 3rd break light mount. These folks seem to have the best; https://acariproducts.com/acaritt/ with a mount that is specific to the ford. It is all aluminum construction and is held in place by locking clamps so it is not grounded (simple fix) The mounting surface is roughly 10" by 22". It also allows the antenna wiring to enter the cab in a sealed environment. I believe I can get a steel top plate for the mount if needed, but I don't want to set up a corrosion problem. There are other 3rd break light mounts out there, but running the wiring is more problematic.

I plan on using another Wilson 1000 or go big and get a Wilson 5000 roof mount antenna, unless I need something different such as a NGP antenna, but I know the range will suffer. The antenna height is actually a plus as it is slightly higher than the 5th wheel (hard wall aluminum frame), so if it hits something I know to stop and check. I plan to mark it with the trailer height.

So will this work? Please suggest away. Grounding requirements, antenna choice, anything of benefit is helpful to me.

Thanks for letting me be apart of your community.

Keith

 

[M0GVZ]

It'll work but poorly compared to most other options because the flat plate of the mount will effectively be the sum total of the ground plane, regardless of however many straps you add.

Mind you given you're getting a third of the distance with 150W than I manage with 4W I'm guessing what you have isn't put in that well anyway so it'll likely work about the same. 7-10 miles range on the road with 150W isn't working well, it's not even working poorly, it's working absolutely abysmally. In fact if that was what I was experiencing I'd be looking to see what was broken.

 

[Shadetree Mechanic]

Welcome! I would go with the hood mount.

 

[Slowmover]

Welcome!!

There’s a thread on the rather expensive brake light mount.

And objection to a proper antenna mount doesn’t make sense. These aren’t 1961 Birdcage Maseratis. Hell, they’re pickups.

My Dad ran a Motorola RadioTelephone in various Buick’s and Cadillacs from 1962 for almost thirty years. They didn’t leak, detract from looks or affect trade-value.

Government and corporate fleet vehicles have been running permanent antennas a lot longer than that.


1). The Bible of Mobile Amateur Radio Installation is:

www.K0BG.com

Every section of this guide is extensive. See “Antenna Mounts” to cover the problems of mobile radio.

No one expects to see you leaning on a ladder with a heavy drill and Unibit. There are professional tools, and excellent other choices to make a clean, uniform cut which he discusses.

2). BREEDLOVE MACHINE makes mounts and antenna-related accessories so fine you’ll tell little wifey you’re buying a few extra as the new centerpiece of the dining room table. (If you had a Maserati, you’d use these).

— An NMO Mount allows use of a baseload LAIRD C27 51” antenna (or LARSEN NMO27). Low-key and good performance if that’s what you want.

— A puck mount on the roof and any 3/8-24 standard flavor CB antenna of your choice. Reinforce the underside and run a quarter-wave if you’re observing 16’ clearance with the 5’er.

— Adaptors can go either way.

I’ll recommend some time reading the problems of inefficient mounts, and on studying the catalog mentioned.

3). As a Peterbilt driver I find it an embarrassment that retired grandmas with a minivan and a cheap mag-base antenna with an on/off button CB will out-talk every pickup out there. As the pickup owners forget it ain’t a Fort Worth Cadillac, but a work vehicle.

The headache rack mounts only work sorta. Fade away fast. Ears no better.

Every other decision is as nothing compared to this.

I’ll stick a cheap Lil’ Wil mag mount on my Dodge pickup roof and out-talk you with a 25W Uniden 76 plugged into the cigar lighter (have done it as a big truck wrangler coordinating 30+ big trucks building an oilwell drill pad one extremely long Saturday).

The vehicle is half the antenna. You cut that down to using an eighth of what you could have had with a bad mount location AND mount, why, you’ll qualify as a Ford owner!

Once more, when it’s time to work, all them Fords have skedaddled; so back a Dodge under to git ‘er dun. Nothing new, here.

Arm & Leg twisting aside, it MIGHT occur to you you want something more than a hotrod CB someday. Do the hard part now. A first class install.

And it might be you have sons and sons-in-law. So you rig up some joke of an antenna on the 5’er with that 95T. And stick a Galaxy 959 in the pickup with an RM ITALY KL203 baby amp behind it. With a 108” whip on the roof.

And when you’ve guided them right to the campground entrance you haul ass out of that drivers seat to get that whip off the roof after telling them you’ll be on the camp road.

“I don’t know, son, this funny antenna on the RV just seems to get out good”.

.

 

[Slowmover]

Welcome! I would go with the hood mount.

You wouldn’t if you had one.
I do, and no one would trade you a can of beans for it.
Talks across the road. Not up or down it.

 

[powerscol]

Welcome!!

There’s a thread on the rather expensive brake light mount.

And objection to a proper antenna mount doesn’t make sense. These aren’t 1961 Birdcage Maseratis. Hell, they’re pickups.

My Dad ran a Motorola RadioTelephone in various Buick’s and Cadillacs from 1962 for almost thirty years. They didn’t leak, detract from looks or affect trade-value.

Government and corporate fleet vehicles have been running permanent antennas a lot longer than that.


1). The Bible of Mobile Amateur Radio Installation is:

www.K0BG.com

Every section of this guide is extensive. See “Antenna Mounts” to cover the problems of mobile radio.

No one expects to see you leaning on a ladder with a heavy drill and Unibit. There are professional tools, and excellent other choices to make a clean, uniform cut which he discusses.

2). BREEDLOVE MACHINE makes mounts and antenna-related accessories so fine you’ll tell little wifey you’re buying a few extra as the new centerpiece of the dining room table. (If you had a Maserati, you’d use these).

— An NMO Mount allows use of a baseload LAIRD C27 51” antenna (or LARSEN NMO27). Low-key and good performance if that’s what you want.

— A puck mount on the roof and any 3/8-24 standard flavor CB antenna of your choice. Reinforce the underside and run a quarter-wave if you’re observing 16’ clearance with the 5’er.

— Adaptors can go either way.

I’ll recommend some time reading the problems of inefficient mounts, and on studying the catalog mentioned.

3). As a Peterbilt driver I find it an embarrassment that retired grandmas with a minivan and a cheap mag-base antenna with an on/off button CB will out-talk every pickup out there. As the pickup owners forget it ain’t a Fort Worth Cadillac, but a work vehicle.

The headache rack mounts only work sorta. Fade away fast. Ears no better.

Every other decision is as nothing compared to this.

I’ll stick a cheap Lil’ Wil mag mount on my Dodge pickup roof and out-talk you with a 25W Uniden 76 plugged into the cigar lighter (have done it as a big truck wrangler coordinating 30+ big trucks building an oilwell drill pad one extremely long Saturday).

The vehicle is half the antenna. You cut that down to using an eighth of what you could have had with a bad mount location AND mount, why, you’ll qualify as a Ford owner!

Once more, when it’s time to work, all them Fords have skedaddled; so back a Dodge under to git ‘er dun. Nothing new, here.

Arm & Leg twisting aside, it MIGHT occur to you you want something more than a hotrod CB someday. Do the hard part now. A first class install.

And it might be you have sons and sons-in-law. So you rig up some joke of an antenna on the 5’er with that 95T. And stick a Galaxy 959 in the pickup with an RM ITALY KL203 baby amp behind it. With a 108” whip on the roof.

And when you’ve guided them right to the campground entrance you haul ass out of that drivers seat to get that whip off the roof after telling them you’ll be on the camp road.

“I don’t know, son, this funny antenna on the RV just seems to get out good”.

.

Thanks very much. It appear sI have a lot of reading to do and get my radio checked out. If I do decide to put a good roof mount on https://breedlovemounts.com/store/ols/products/nmo-roof-mount, can you recommend a good antenna (assuming the radio is between 50 and 150 output (its actually variable)

Thanks everyone

 

[Slowmover]

Thanks very much. It appear sI have a lot of reading to do and get my radio checked out. If I do decide to put a good roof mount on https://breedlovemounts.com/store/ols/products/nmo-roof-mount, can you recommend a good antenna (assuming the radio is between 50 and 150 output (its actually variable)

Thanks everyone

“That’s MY radio power range! Who said you could use it?!”

I think 50-150W covers realistically what CB Radio can do while mobile. Even with long-distance SSB exchanges. It’s the antenna (system) where any difficulties should be, not Queen Mary dockside power cabling.

I’ve mentioned above (2) near-identical antennas that government or corporate fleet users would specify. A bit over four-feet, and low-key otherwise. Should survive the occasional whip strike. On my 2WD Dodge they’d take me to about 10’ as clearance restriction (I use 14’ on the Peterbilt).

I tend to subscribe to the “minimum” as being a 5’ antenna. Longer is better, and Height is Might. The trade offs come with where to mount.

I’ve a number of antennas at home. The 5’ Skipshooter (and 6’ plus 7’ versions) I’d highly recommend to anyone. An inexpensive topload American-made fiberglass whip. GP, for my uses. (Recommend the Natural color).

I bought a President (brand) Texas last year (7’) a 3/8-24 baseload that’s been my idea of what I want for the roof-center Breedlove Mount. Does put me at needing a 12’ 5” clearance, but I don’t do much in the way of normal commuting hazards.

The best CB antenna is the old reliable 102” SS whip (17-7 stainless, IIRC) that would put me needing right at 15’ clearance and it’s a heavy wind load. I’ll build/install the mount for this antenna as it’s the performance baseline for all others.

One of the best known (and best performing) open coil antennas is the modular Predator 10k which can be assembled in a variety of heights. (Advice is recommended).

I’ve had several of the Wilson 2000 (not its bigger brother 5000), and I know of no one unhappy with them. Both easily found.

One I plan to get is the Sirio 3/8 Trucker which is similar to the Wilson in basics. Sirio usually gets the edge over Wilson per reviews.

These last three meet the 5’ mark handily where attention to shaft length, etc, is specified. One can go longer, too. This would bring my pickup to about 11’ in needed clearance.

A word about antennas:

1). Storage & Transport should be addressed at the same time as purchase. Whether a capped PVC tube or other, one should only have the antenna out of its case while in use. Not leaning in a corner or laying in the truck bed when off-duty. Laminate the paperwork and attach to case in some fashion.

2). Antennas need their own dedicated bag of spare parts & tools. One per brand, or (literally) one per antenna. I think it’s obvious. “why”, if we take seriously our ability to communicate at a distance.

Corrosion builds on antenna mount threads, they may need metal polish, etc. Brass toothbrush + Flitz. (Etc).

3). The antenna system may need attention at any given time. So Radio as a whole needs dedicated tools, supplies, and bag (transport case), not rummaging through the truck or RV or house or work tool bags or boxes. (I like the Bucket Boss brand. They don’t wear out. Then zippered envelopes or Ziplocks) .

4). That Galaxy DX95T needs its own: A Harbor Freight Apache 3800 pick & pluck foam-lined transport case which would carry all items originally sold with the radio plus an external speaker, spare mic and fuses. The originals and extras belonging to that particular radio (and no other).

The installation is greatly aided where organization comes first. The antenna may change. Plus spares needed. Etc. Have ways to keep items safe & separate.


.

 

[powerscol]

“That’s MY radio power range! Who said you could use it?!”

I think 50-150W covers realistically what CB Radio can do while mobile. Even with long-distance SSB exchanges. It’s the antenna (system) where any difficulties should be, not Queen Mary dockside power cabling.

I’ve mentioned above (2) near-identical antennas that government or corporate fleet users would specify. A bit over four-feet, and low-key otherwise. Should survive the occasional whip strike. On my 2WD Dodge they’d take me to about 10’ as clearance restriction (I use 14’ on the Peterbilt).

I tend to subscribe to the “minimum” as being a 5’ antenna. Longer is better, and Height is Might. The trade offs come with where to mount.

I’ve a number of antennas at home. The 5’ Skipshooter (and 6’ plus 7’ versions) I’d highly recommend to anyone. An inexpensive topload American-made fiberglass whip. GP, for my uses. (Recommend the Natural color).

I bought a President (brand) Texas last year (7’) a 3/8-24 baseload that’s been my idea of what I want for the roof-center Breedlove Mount. Does put me at needing a 12’ 5” clearance, but I don’t do much in the way of normal commuting hazards.

The best CB antenna is the old reliable 102” SS whip (17-7 stainless, IIRC) that would put me needing right at 15’ clearance and it’s a heavy wind load. I’ll build/install the mount for this antenna as it’s the performance baseline for all others.

One of the best known (and best performing) open coil antennas is the modular Predator 10k which can be assembled in a variety of heights. (Advice is recommended).

I’ve had several of the Wilson 2000 (not its bigger brother 5000), and I know of no one unhappy with them. Both easily found.

One I plan to get is the Sirio 3/8 Trucker which is similar to the Wilson in basics. Sirio usually gets the edge over Wilson per reviews.

These last three meet the 5’ mark handily where attention to shaft length, etc, is specified. One can go longer, too. This would bring my pickup to about 11’ in needed clearance.

A word about antennas:

1). Storage & Transport should be addressed at the same time as purchase. Whether a capped PVC tube or other, one should only have the antenna out of its case while in use. Not leaning in a corner or laying in the truck bed when off-duty. Laminate the paperwork and attach to case in some fashion.

2). Antennas need their own dedicated bag of spare parts & tools. One per brand, or (literally) one per antenna. I think it’s obvious. “why”, if we take seriously our ability to communicate at a distance.

Corrosion builds on antenna mount threads, they may need metal polish, etc. Brass toothbrush + Flitz. (Etc).

3). The antenna system may need attention at any given time. So Radio as a whole needs dedicated tools, supplies, and bag (transport case), not rummaging through the truck or RV or house or work tool bags or boxes. (I like the Bucket Boss brand. They don’t wear out. Then zippered envelopes or Ziplocks) .

4). That Galaxy DX95T needs its own: A Harbor Freight Apache 3800 pick & pluck foam-lined transport case which would carry all items originally sold with the radio plus an external speaker, spare mic and fuses. The originals and extras belonging to that particular radio (and no other).

The installation is greatly aided where organization comes first. The antenna may change. Plus spares needed. Etc. Have ways to keep items safe & separate.


.

Thanks Slowmover. Sorry about using the link. Now back to more reading and thinking

 

[Big Kahuna]

If you're against drilling a hole and the body is aluminum and a magnet mount won't work then you are left with a couple of options.

- The brake light mount you mentioned probably isn't going to work very well because it would likely have rubber molding around it so you'd be relying on it as your ground surface.

- A fender mount might work ok as long as the mount itself is grounded to the frame really well which is pretty easy to do inside the engine bay. Honestly this is the easiest way to start. Just a fender mount ($20) and some ground strap and an antenna. Cheap way to start and then you can test and see what you think.

- A tool box or headache rack behind the cab can do ok as well as long as they are grounded really well to the frame. I've done this before with a steel box that had two straps running to the frame. It wasn't terribly directional and I mounted a coil antenna on the steel box and ran around 350 watts. The key is to get the antenna base up near the height of the cab roof if possible.

- A stake hole mount could be used but again you'd have to ground to frame really well and it would be fairly directional.

- You could fabricate a bumper mount. I've done this on a vehicle where I built a very heavy duty steel mount that I put on the right rear of a SUV and it stuck out about 6" past the vehicle. It bolted directly to the frame so my ground was amazing and super low SWR. I then used a 102" steel whip off the back. Because of the placement the antenna was directional towards the front of the vehicle like 70 % more signal out the front than back. I ran a fairly large amp with this setup and could talk out the front of the vehicle very well - if you were behind me though it didn't work as well. For DX I'd drive down to the shore and point my SUV towards the mainland. The nice thing about the setup was it was easily removable . The bad thing (aside from the directional issues) you didn't want to bang your shin on the mount as you walked by

Lots of ways to try. Grounding will be your biggest issue - have to get ground strap to the frame where ever you decide to mount likely. Make sure you have a good meter so you can check for a low SWR.

 

[Slowmover]

“Ground” in this case is RF ground (not the same as DC ground). Easiest, IMO, to refer to DC as “ground” and RF as “bond”.

 

[Slowmover]

Thanks Slowmover. Sorry about using the link. Now back to more reading and thinking

Mr Applegate (K0BG) did a tremendous amount of work, and it’s of better quality than maybe we deserve.

I’m not that far down the road you’re starting. Have made it to Bonding which has become its own project.

An earlier project found me finally buying Anderson PowerPole supplies and tools. Wish I’d done it years ago.

I’ve big truck, pickup truck and travel trailer in which to do installations. Then there’s my sons vehicles and home.

So, . . I look at these indirect expenses as being a way of paying myself. I’m better equipped.

I’m saying, Don’t be thrown off by tool & supply!

.

 

[Big Kahuna]

Yes as Slowmover specified I was describing bonding your antenna system to your frame using ground braid/straps ideally at the largest width you can afford/fit for RF grounding.

Some keys to antennas on vehicle - and you should do some reading in the antenna section here on the forum as there have been lots of discussions and photos.

- Height is might - ideally get your whole antenna to the top of your vehicle. Roof mounts generally are the best spot.

- Antenna length - the longer the antenna the better in most cases. 102" whip is best, then long antennas like President Texas, Sirio PL5000, Wilson 5000, Predator 10K.

- Avoid blocking antenna radiation - don't mount an antenna right behind the cab - try to get it above the cab roof if you mount there. Some people have done this with extension rods.

- Center of the vehicle - try to mount closer to the center mass of the vehicle. If you mount on a corner or on one side the system becomes directional. Rear left mount will radiate towards front right etc. There are some great overhead pictures of this -

- use quality coax and don't pinch it anywhere in doors etc

- Check your SWR using an external meter or antenna analyzer

- Ground/Bond your antenna mount as best you can to vehicle. Bonding to frame is best.

 

[powerscol]

Yes as Slowmover specified I was describing bonding your antenna system to your frame using ground braid/straps ideally at the largest width you can afford/fit for RF grounding.

Some keys to antennas on vehicle - and you should do some reading in the antenna section here on the forum as there have been lots of discussions and photos.

- Height is might - ideally get your whole antenna to the top of your vehicle. Roof mounts generally are the best spot.

- Antenna length - the longer the antenna the better in most cases. 102" whip is best, then long antennas like President Texas, Sirio PL5000, Wilson 5000, Predator 10K.

- Avoid blocking antenna radiation - don't mount an antenna right behind the cab - try to get it above the cab roof if you mount there. Some people have done this with extension rods.

- Center of the vehicle - try to mount closer to the center mass of the vehicle. If you mount on a corner or on one side the system becomes directional. Rear left mount will radiate towards front right etc. There are some great overhead pictures of this -

- use quality coax and don't pinch it anywhere in doors etc

- Check your SWR using an external meter or antenna analyzer

- Ground/Bond your antenna mount as best you can to vehicle. Bonding to frame is best.

OK I hope I don't show how dumb I am with a few questions. I'm a retired Civil engineer - college electronics class was very hard for me, but if it is AC house wiring I know some.

First I hope I can clarify some things. With the fifth wheel in tow I cant use any bed mounts, or I believe a headache rack due to clearance. In the past I have also tried a front fender/hood mount and had issues including badly denting the hood. Lousy reception and engine static too even with filters, etc.

The third brake light mount is indeed isolated with foam padding/rubber seals. It can be grounded to the cab using one of the original brake light screws holes or several if needed. The mount and cab are aluminum, so I would use aluminum wire. I believe I can also get a Bonding strap to the frame from the mount through the cab, but I probably need to shield the bonding strap inside the cab to prevent corrosion if it touched anything, unless I use aluminum wire again, but as frame is steel probably best to go with copper flat braided cable and isolate it from the cab surface. Thoughts?

Would having an 18"x10" steel plate under the antenna as part of the mount help?

Now the last question. The cab and the pickup box are grounded to the frame or is it bonded, I believe. I have seen braided straps at both bed and cab locations, including engine block to frame. I have crawled under several checking them out. So why dose the pick up box not act as a ground plane too for the antenna as it is under the base of the antenna. Or does the ground plane need to be in fiscal contact with the antenna base?

Oops one more. For a center roof mount (if I go that way) is a base coil antenna better than a mid coil antenna (Wilson 2000 as example)? I'm still thinking of the Wilson 5000 as it is US made per manufacturer. I know there is probably a wide roof mount that could handle the extra stress of the Wilson 2000 if needed. I am concerned about having the cab roof deform. as for antenna high a 1/4 wave seems to be about right at 5' something (62"?) My trailer is 12' - 6" to top of AC unit. roughly 11'-9' to roof. Construction is fiberglass bonded to an aluminum frame and sub frame that is attached to the steel frame and running gear.

Now if I am totally off here please let me know - just trying to wrap the gray cells around all of this. Now if you want to laugh - back in early college days I had a home base station with a huge fancy non-directional roof antenna (state of the art for mid 70's) I had a different side ban radio and talked all over the country on about 50 watts.my mobile vehicle was an IH scout II with co-phases dual 102" whips that were body mounted rear fenders. Strange how times make you forget the details, but I do remember my old CB license number KDA 99 something something. It will come back to me after I hit send.

I cant thank everyone enough for the help on this.

 

[Big Kahuna]

Ideally you want the antenna mount in direct connection with the ground plane surface that's why drilled mounts tend to do better than an antenna on a fender mount that then is touching paint or isn't really connected well to the metal surface. That's why for a fender mount I suggest running ground strap to the frame as well.

That's just an example.

The 3rd brake light mounting is just problematic because it's not really a direct part of the vehicle. It has rubber gaskets etc. which isolate it. If the metal surface of it is connected to a grounding wire that runs to frame that would be better, but your antenna is connected to a plate that is connected to a wire that is then connected to your frame or body, not really a direct connection.

The aluminum body should still work the same as a steel body car in terms of acting as a counterpoise/ground plane surface. The key for you is the get the best contact between the antenna mount and the metal body.

Could your 3rd brake light idea work? If you use a metal plate and it's connected really well to the rest of the truck then possibly. Just may take some work and fiddling but also you have to not be surprised if it just doesn't work out all that well.

That's why I suggested a fender mount as a cheap simple starting point. No holes to drill, uses existing bolts under the hood in many cases, it should fit properly between the hood and body and not dent anything. Use a base load whip antenna for a fender mount to keep wind load down.

It's a cheap starting point. My roof mount magnetic mount Wilson 5000 is better than my fender mount (64" whip base load antenna Radio Shack 21-988) I had on the same vehicle, but I also was able to talk 50 miles locally on occasion with my fender mount and 100 watts so it's wasn't anything to complain about but it was slightly directional. Tons of ham and CB users have fender mounts and they do fine. Neither of those setups outperformed my 102" or Predator 10K hard mount though.

The big problem with newer cars is the pieces aren't always connected together the same way they used to be in older cars. Cabs can be isolated from the frame for a softer ride which is nice for driving but bad for CB antennas. Some serious CB users bond all of their body pieces to the frame and each other with strap but that is overkill for most people.

You'll probably have to just do trial and error. If you really like the idea of using the brake light adapter then go for it, but be aware it make take some work to get it grounded well to the body/frame.

Best antennas mentioned - Wilson 1000, Wilson 5000, President Texas, Sirio 5000 PL, 102" whip, Predator 10K.

Also I believe you mentioned copper and I don't think you're supposed to use copper and aluminum together because they can corrode faster? Someone else might remember why this is.

 

[powerscol]

Ideally you want the antenna mount in direct connection with the ground plane surface that's why drilled mounts tend to do better than an antenna on a fender mount that then is touching paint or isn't really connected well to the metal surface. That's why for a fender mount I suggest running ground strap to the frame as well.

That's just an example.

The 3rd brake light mounting is just problematic because it's not really a direct part of the vehicle. It has rubber gaskets etc. which isolate it. If the metal surface of it is connected to a grounding wire that runs to frame that would be better, but your antenna is connected to a plate that is connected to a wire that is then connected to your frame or body, not really a direct connection.

The aluminum body should still work the same as a steel body car in terms of acting as a counterpoise/ground plane surface. The key for you is the get the best contact between the antenna mount and the metal body.

Could your 3rd brake light idea work? If you use a metal plate and it's connected really well to the rest of the truck then possibly. Just may take some work and fiddling but also you have to not be surprised if it just doesn't work out all that well.

That's why I suggested a fender mount as a cheap simple starting point. No holes to drill, uses existing bolts under the hood in many cases, it should fit properly between the hood and body and not dent anything. Use a base load whip antenna for a fender mount to keep wind load down.

It's a cheap starting point. My roof mount magnetic mount Wilson 5000 is better than my fender mount (64" whip base load antenna Radio Shack 21-988) I had on the same vehicle, but I also was able to talk 50 miles locally on occasion with my fender mount and 100 watts so it's wasn't anything to complain about but it was slightly directional. Tons of ham and CB users have fender mounts and they do fine. Neither of those setups outperformed my 102" or Predator 10K hard mount though.

The big problem with newer cars is the pieces aren't always connected together the same way they used to be in older cars. Cabs can be isolated from the frame for a softer ride which is nice for driving but bad for CB antennas. Some serious CB users bond all of their body pieces to the frame and each other with strap but that is overkill for most people.

You'll probably have to just do trial and error. If you really like the idea of using the brake light adapter then go for it, but be aware it make take some work to get it grounded well to the body/frame.

Best antennas mentioned - Wilson 1000, Wilson 5000, President Texas, Sirio 5000 PL, 102" whip, Predator 10K.

Also I believe you mentioned copper and I don't think you're supposed to use copper and aluminum together because they can corrode faster? Someone else might remember why this is.

Thank You for the help
Keith