40K,
I didn't read all of the advice here, So I apologize in advance if it has already been mentioned.
You can have the best materials in the world, but if you don't know the proper TECHNIQUES, you are wasting your time.
DO NOT WET SAND IN A SWIRLING MOTION. Wet sand the car in straight parallel strokes aligning the stroke along the longitudinal axis of the car (front to back) Maybe you are swirling???
When you are compounding the car the same applies: (whether it be by hand or with the buffer) work the same direction as the sanding. Think of the car as being a piece of wood that has the grain running from front to back. Every step should "go with the grain"
Wet sanding and polishing a car is not something that can be easily taught with words. If I were you, I would go to a body shop walk directly over to the employees tell them about your Cobra (bring pictures to get 'em interested) and see if you can get one to come over your house after work and teach you. I'm sure there is someone out there that would do it just because they think your car is cool.
While your at the shop, ask them if you can take a hood or something from the pile of crashed parts out back. Practice on that instead of you car. get a black one if possible. If you can polish a black car you can polish anything.
Oh, and remember "don't do the edges they do themselves" I can still hear Otto (my old boss) saying that to me
Steve