Posted: Wed Feb 17, 2010 8:23 pm
Most of the holes I see in your photo are factory. The large one in the front of the bed (with cover around it) is power feed to radio systems, usually found only on earlier trucks. What year is your truck? The set of holes on the side are for radio antenna mounts. The larger one is for the antenna cable to go through, the smaller ones are bolt holes for the mounts. If you would like, I'll try to get some photos of mine, but might be a day or so.