HJ, and others, here is a pic I promised a couple weeks back of some headers that I used a product called Blue-Away on. They are about 15 years old. There are some water spots on them that you cant see, and they aren't mint by any means, but they aren't blued either. At one time they were however and the product removed most of it. Have to use it sparingly as it is removing chrome, you can see that near the head, on the top of the tube it isn't blue or chrome, just dull grey. They also have a bit of a gold color to them, not that deep mirror look they have when new.