I noticed the other day that the stock pipes I had gutted are rusting pretty good on the inside. Not sure how far back it goes, but at least at the back end of the pipes. Thinking of picking up a Dremil tool to carefully grind the rust away. (other suggestions?) But afterwards, any recommendations on what I can do to preserve my pipes?

2005 America, green/gray, gutted stock pipes, tall sissy bar w/ luggage rack, Saddleman's dual touring seat and Tourmaster saddlebags (and sissybar bag).