Getting ready to order some caps and other components for a rather dingy MS2930 chassis. Unfortunately, the trimmer pots are thoroughly rusted and very much stuck (I tried to turn one, and it wound up breaking). My intention is to just replace them, but I was wondering - should I also replace the rusty factory set pots (like B+ and X-ray protection), or as long as they are still intact, would it be a better idea to just leave them as-is, since I have no intention of ever adjusting them?