I want to restore my crx.
Questions
How much sanding do I need to do when a car has had 2 paint jobs? The original color can be seen after chipping some of the 2nd paint job

When using bondo, how much paint am I suppose to sand off my car before applying bondo.

 

just make sure theres no clear coat on it... or you can sand straight down to the metal

 

Sand the clear coat down, then sand a little bit of paint, you should be good. If there is rust, it must ALL be gone, all the way to the metal and up to and including 4-6 inches from rust, to prevent any spreaded rust under the paint.

Remember, bondo is a body filler, not maker.