So, just registered and might as well jump into the questions. I will be replacing the front clip and cab of my truck very soon. I do have an entire front clip sitting in my driveway now, and that's one of my hang ups.
The fenders do have very minor surface rust so i want to strip them to bare metal and kill rust before it becomes a problem. I was going to just sand and wire wheel them down but then I thought of the insides. The insides could very easily fill with water/crud and sit rusting away and I would be none the wiser. What can I do about that. could I just poke around with a mirror to see if everything's ok then fill them with expanding foam? Or do I have to have them done professionally?
From what I have found, the right bed liner can make good undercoating/rustproofing. Am I right in this assumption? I am planning on doing the underside of the cab, floorboard, rockerpanels, wheel wells, and a stripe around the bottom of the body and maybe around the fenders. Mostly on some of the rust prone areas, just to be safe. And can bed liner be sprayed/rolled/brushed on top of paint or should I do primer -> liner -> paint?