Knowing how much mud etc: gets throw up onto the sides I made some fender flares for the rear. I made the frame first to beable to mount my flares too. Under the box there is a place along the outer frame ,at the top and bottom that you can drill through just the frame and still beable to put a nut on between the under side if the box floor and the top of the frame.Let me tell you it's tight but doable.
