the paint around the mouth of the gas 'inlet' (under the gas cap) on my '03 speedie is bubbling/peeling. I know that some with newer bikes have had this issue and have gotten warranty replacement..unfortunately this isn't an option with my bike.

I'm wondering what the best approach here is..? I'm assuming that the best thing to do is to peel off any loose paint so that it doesn't come off on its own and fall into the tank. under the paint there is bare metal. Should I coat the metal with something (eg. touchup paint) so that the metal doesn't rust? if so, what's the best thing to use?
or should I leave it alone altogehter?