Thanks Robert...Thank you for your reply.

It was notebook paper and it cleaned them up pretty well and lasted for about a year. I think emery paper with non metallic abrasive would be my next try and then do the OE voltage adjustment. I have 1 follow on questions.

1. Do you happen to know which parts house brand will accept the stock cover?

I have a date coded electronic replacement from Year One, but I would really prefer to use the mechanical one with the stock cover if possible as the one from Year One is not really correct.