What are you guys doing in those hard to get to areas like boxed in sections of framing and sheet metal where you have absoloutely no access other than the 1" diameter drain holes? I've got a lot of boxed in areas where I can see there is a bit of dirt and a small amount of surface rust but I have no way of getting to it without going overboard and drilling out 1,000,000 spot welds needlessly. Like inside solid frame rails. Seems a shame to have the outsides get a nice layer of epoxy primer but not be able to get at the insides. What are you guys doing in these areas? Pressure wash as best I can and live with it? Try and get some phosphoric acid coating in there??