I just got one of the rotating Ford bed extenders and have run into an issue. The previous owner of my truck had a spray in bed liner put in, but they didn't bother to cover any of the holes in the bed of the truck before they sprayed it in. I need to get a tap to clean all the crap out of the threads so I can screw it in. Does anyone know what size and thread these holes are? Any idea how to clean the liner off of the rim of the non threaded holes above and below as well? I've tried using a razor, but that is some though stuff!