I can get a pic like that in a couple days. But untill then, this might help answer your question-
If you're familiar with the factory plastic rocker panel covers, they're the same as those, they're molded to match up to, and utilize the center piece. They mount using 2-way tape around the top edge(I'd recommend 3M) and screws underneath, very similar to a body kit on a car. When I was going to use them(before the truck broke) I was going to trim off that bottom part that goes into the rocker panel as I had started a box tube rocker panel replacement.