One Marine to another... Don't *&^% it up by trying to restore it, it's only original once. A simple soaking in a oil bath and wiping away the excess is about the best you can do from here. Otherwise it could cost you big money and a servere loss of value. Best wishes and welcome to the Colt Forum, you'll meet some of the finest Colt Collectors in the world right here and be able to get some advice from them. What's not to like?