I have a 77' with the 1800 badge. Since I got the car a few years ago the badge has been very dull around the numbers. The numbers themselves are shiny, but the rest of the badge wasn't. This afternoon I tried using some Mother's Back to Black and an old toothbrush and voila, the color around the numbers returned. I know that product is designed for plastic and rubber, but it worked great to bring back the dark color in the badge. I think I'll give it a quick once over tomorrow, but the badge looked almost brand new.
See, not super helpful, but I do what I can.
