There was no center sill on mine. As I recall there are two hard rubber pads that it sits on at the highest point on the frame (just forward of the rearend).
As for taking off the side pieces... it's a one-time deal and not pretty. I used a drill bit and a chisel and a LOT of sweat. Unfortunately the bedside sheetmetal is the weakest link in this case and I got several tearouts. It didn't matter on mine due to many mods to the bed and floor but because your truck is a ground-up deal, you might not want that to happen.
Good luck with it!
Kenneth
|