The "boxes" take the long bolts that go through a wood bed slat with an acentric drilled hole and a star washer to "lock it in place" then through the hole to line it up and then through a block of wood that keeps the bed off the frame, all the small drilled holes are where the bed wood bolts go through, a pre drilled wood bed set was pretty easy to install. If you look at my flicker link it might give you a better idea. I used POR 15 on mine to stop the rust process. Good Luck, John
