OK, I had to go over the schematic, and the ones on CBTricks are hard to read. I'm not that good at understanding what everything in a circuit does, but here's my take:
Steps 7,9 go together. They change the circuit values around the Audio power amp and the AMC (modulation control) transistor. Basically it's widening up the audio response and allowing the radio to modulate a little more free.
Step 8 : Not sure I understand it, but it looks like it's the first resistor on the collector of the final transistor just past the low pass filter. Adding more resistance to ground at this stage seems to me like it would allow more current to flow through the final to the load (antenna). This part of the mod is eliminated with the MOSFet mod.
Step 3: Not sure...it's supplying more capacitance to the audio IC, but since I don't have a pinout handy of that IC, I can't be certain what part of the IC it's affecting. I'm guessing it's just providing a little more sustained drive to the driver and final.
Maybe someone who understands the circuits better than me will come along and help me out.
You can't change the driver to the mosfet if you're going to do this mod. You need to do one transistor design or the other but not combine them.
However, it looks to me like you could do steps 3,5,7,9 with the mosfet mod. Regarding the output coil: It doesn't really matter which side you remove it from; you'll have plenty of adjustment range once you have the correct number of turns. You should be able to do this with the mosfet mod also and fine tune the output a bit better than just discarding the slug.
If you do this, let us know how it turns out. I've been thinking about trying this out myself but just haven't gotten around to it yet.
