I have a headache rack on my truck. I built it rite after I bought my truck. I built it with bed rails that go down the hole lenght of the body. I have 2 back up lights and 1 strobe light on it. I like having so I can't put a peice of fire wood or my ATV through the back window. My camera is broke, so when I get a new camera I will take a few pictures of it.
I currently have one on my F250 and have the same form of side rails that you do, but I will have to rebuild it.
I was talking to an auto body shop yesterday and it seems that the weight of the rack is hard on truck beds. Over time the rack can cause the corners of the bed to start cracking. That is what is happening to mine.
The fix is to build the headache rack so that it bolts to the
frame of the truck.
Essentially that requires the construction of two "U-shaped" supports. These supports are bolted to the frame of the truck (on the truck bed), run up the sides of the bed, and provide a place to bolt the headache rack (bolts allow for easier removal of the headache rack).
This causes the weight of the headache rack to rest on the frame of the truck and prevents cracking of the truck bed.
HTH