Thanks for the idea! Only thing I did differently was use Bar Keepers Friend instead of Comet. Cleaned the metal work just enough, without putting a high buff on it, that you get with metal polish. Just got rid of the tarnish. Also, did not damage the original paint.
Hey Harry, your video was exactly what I was looking for. I have 3 Lionel tin plates arriving today. Suspect they will need the same treatment. Thanks a bunch!