Leth, Just get a piece of 1/2" OSB and cover the back 4 feet of your bed, for $13 you have a half tonneau cover. I make a block of wood that fits inside the "Stake Holes" in the rear of the bed, you can lock it in place by putting a screw in the side of the block, then just run a screw down into that from the top, through the OSB. For the front part of the OSB you could use C clamps, or just make wood blocks to act as clamps with big screws again. It would only take a minute to get on or off once you have it figured out, and it would be a good aero enhancement.
