So I had the same problem, and first of all you don't need to tap the holes for the screws. All you need is a small flathead screwdriver to clear the bedliner out of the threads. I don't remember the bolt size that you need, but the bolt that is the closest to the top of the tailgate on the tailgate latch is the same size. I took it to home depot and got 4 of those and some washers, and it bolted right up. The boltswill take a little bit of torqueing to clear out all of the bedliner, but they seat nicely. Hope this Helps!