Yesterday, I tried a new rust removing product called Envirorust Rust Remover on some of the 1963 Chrysler parts. After soaking the radiator fan shroud in the solution for about 24 hours, it removed all the rust and rust scale down to bare metal, but didn't harm the factory paint that remained on the part for for the last 46 years. I was very pleased with the product, and since it is also non toxic, biodegradable, and water soluble, it is perfect for restoration use. What makes this product even better is that it has a mild de-greaser in it also that will cut through the thin layer of grime that might be left after you do the basic cleaning of the part. I also put the bolts into the solution, and they were very rust encapsulated, and they came out with the original black oxide finish that was originally used on these parts. This is because after the Envirorust product removed the rust, it continued to draw the carbon to the surface of the metal, without harming it. After removing the parts, I washed them down with cold water, and a soft bristle brush to remove any residue of the product, and then set them in the sun to dry. Now, all that is left to do is to prime and paint them.