Thanks for the advice Frank
. I have been contemplating a simple cap for the bed. Not being a real "design guy" and having limited fabbing skills, (but great pipe bending skills. I'm an electrician) does an aero-cap need to be all "swoopy" with rolled edges or would something with some right angles still be workable? Imagine a rectangular box, cut down, with a sloping horizontal plane for the top. Where the sides meet the top would be 90 degrees, but with a sloping plane at 12 degrees from the bed.
As a side question--- How in the world did someone figure out that 12 degrees was the right angle? It seems I read it somewhere that 12 deg. was optimal but how it was decided I can't remember.
Anyways, thanks again for the help.
Hat_man