stepside rust issues

[rookierodbuilder]

Those of you in the central-northeastern U.S., have you run into the same problem as I with rust starting to form around the fender lip on step-side bed trucks? My truck is about to turn ten, and other than this annoying rust issue, it looks great. Has anyone here made a repair on these step-sides and if you did, how did you prevent future rust out? My guess is factory made holes in the inner fender have allowed all kinds dirt, salt and water to accumulate and start rust. I figure I'll rob good fender lips from a donor and plug the factory holes as i go. Sound like a good plan?