Since I've had the fiberglass top off for the summer, I decided to cut the sliding windows out and replace the metal trim pieces. A couple of years ago, I bought some like new, rust free trim parts off ebay. They had no signs of rust anywhere. Not one spot of bubbling. The only thing was the black coating was faded. So I decided to remove that stuff, and it is tuff. I wanted to go to bare metal and put metal etching primer on before repainting. To my surprise, there were very small, snowflake shaped little rust spots starting.
so I lightly sandblasted the whole thing.
primed, painted and reinstalled.