how to make dog dish hubcaps shine

Maybe the wrong place to post, but I'm sure some of you have done this. The caps look great, but they have sit on the car forever. They are not dented at all, just dull. What should I use and what process to make them look good? If you know of a product to start with let me know. I have an extra one I tried some wheel cleaner and polish, but it didn't really do any good. Hopefully when I'm finished I will run these with Chrome trim rings. That seems to be what came on the car as far as I can tell.
As always thanks for your help.