Welcome 49oldandslow. Very nice truck you have. I don't see anything wrong with your plan, in fact I have almost exactly what you intend to do. I have a stovebolt six, 261 engine, 4 speed, kept the generator and went 12 volt. I changed out the rear for a 3.55 in the old torque tube setup. My suspension is stock and works well. I also have the drum brakes with single master cylinder, not the best brakes but I'm used to them. Instead of A/C, I open the window and have the cowl vent but we don't get the crazy temperatures you get. I have tall, skinny bias plies which is not good for handling or high speed cornering, maybe should have went radials.
Leo
