Rebuilding an old 4 door belair. The body has some rust(just surface rust) and has a few small dings. I am an auto body TECH so it isnt a problem to fix the body. But i have a question. Should I grind all the paint off, down to the metal and put a think coat of Plastic(bondo) on the ENTIRE car, or should i just grind down the dented spots and bondo small areas? I figured it might be worth doin the whole car to take care of ALL and any low spots. What do you all think?