Protecting surface that has small surface rust already?

Okay as some of you know I bought a 70 Duster as a "long term" project. The car has some surface rust. Here is my question. I really don't plan to get fully started on the car for a couple of years(as I already have a 71 Dart in the bodyshop). Anyway I would like to "protect" the Duster against getting any worse. What should I do? Is there a product that I can put on the areas to keep them from getting worse? But keep in mind, whatever I put on the car will have to be stripped of and painted over in the future. :scratch: