I have some surface rust under the rubber seal for the trunk of my chevelle. I was thinking of sanding the surface rust off and putting Por 15 on the areas I sand. Is this a good idea? Does anyone have a better solution to stop the rust?

What rubber seal??? Are you refering to the mat??? At either rate, all rust needs immediate attention. Surface rust becomes a promlem if not addressed.

I think he's referring to the trunk weatherstrip.