Okay cool I'll give that a whirl and see what happens.
As promised I am back now with some more info on a mosfet conversion. There's something acting funky and a few things getting hot along the way, more on that in a second. This is what I came up with for a mosfet conversion thus far. These aren't the final numbers and they could change moving forward.
Remove: c105, r113, r112, L9 and the 470 ohm that is parallel to the RF choke feeding the drain of the mosfet
Replace:
L8 4.5t close wound on a slug Tower from a parts pig
L10 4.5T more spread out on a slug Tower from a parts pig
C107 4700pf bypass cap
C103 390pf
C104 220pf
C108 300pf
Companion part consists of 470 ohm inline with 4148 diode and landed on 2.7k ohm for the ground to gate shunt similar to the en1230 companion part (which uses 3.3k)
Now the fun stuff.. I get a squeal anytime I set the dead key above three Watts, and it gets more pronounced the more I get long keyed. Transformer itself gets really hot after a while. I think the mosfet is pulling a little too much juice for the transformer to handle. I don't think it was made to handle anything above the 10w pep it came stock putting out. Everything sounds the best (least worst) when I have the carrier set around 3 and swinging up to around 25pep before everything heats up. I think there's a couple different ways I could attack this,
one of them being take the final + feed rfc off of the modulated line downstream from the audio transformer and simply attach it to the main 13.8 volt line. The modulation can be handled all by the driver, with the final mosfet setup like a linear, possibly even supplying it with some bias voltage
Another option would be to lose the transformer and go with a big Darlington regulator.
I guess I could parts pig a transformer from another radio but.... There's the chance I would have the same results as I'm currently getting with the overheating and squeal