Eagleeyes I will toss some things out there for you to consider and understand.
1) Amplifiers are illegal just so you realize that.
2) The antenna is the most important part of the system. Your Wilson 1000 is fine. I will assume you have already properly mounted the antenna and set the SWR.
3) You will want a shop to properly tune your radio. Have them set the AM dead key for 1.5 watts or install a variable dead key control so you can go from say 1.5 - 5 watts.
4) Choose a nice small 2 pill amplifier like a Texas Star 250, Midnight Special 250, or a KL300 just to list 3 choices.
5) You will need to do a good install on the amplifier, #10 or #8 wire, fuse by the battery and at the amp. Solder all connections. Run a 6 foot jumper. Red power line goes to the battery, ground to the floor or firewall.
I would also suggest you get a decent watt meter so you can keep tabs on what's going on. Each amplifier will have small differences in what drive levels they need to work right and so you don't burn the amp up. Most people dead key too much wattage into their amplifiers.
What version of Cobra 148 do you have? If it's one of the brand new radio's I would suggest you get a different radio before you even start. The new 148's are poor performers.