Forgive my lack of clarity on the Evapo-Rust. I agree with Don on it not removing the rust Stains from painted surfaces and his comment with regard to using Brass or Bronze Wool. Attahed link shows the 'Before' and 'After' of an item of mine that had corroded through the Chrome Plating. The item was not worthy of the cost of replating but from a distance is much more presentable.
http://s517.photobucket.com/
Jay Dubiel
Halifax, VA USA