I did this...



Bought the fog lights at WalMart for about twenty bucks. Mounted them on the tonneau brackets, ran the wires under the rails, then through the rear hole in the side of the truck bed. Then I cut the four prong off an old uhaul adapter, and plugged it in to my trailer hitch. In order for the lights to work, I need to have my parking lights, or lights on. There is a switch that the fogs come with. I mounted it to my bed. If I need to take the tonneau off, I installed male/female plugs where the wires go from the tonneau to the bed rail.

 

Nice set up, looks good. I have a soft cover roll up however, so cant mount anything to the actual tonneau cover.

Upon further looking at my bed just now..
I have about 16inches between the front of the bed to the first clamp, then another 16 inches between the first and 2nd clamp, then 24 inches between the 2nd and 3rd clamp.

Now to make things more interesting if you look up under the rail you will find the plastic clips that hold the plastic bed rail covers on.

So I guess I need to figure out how the heck to make this work...

 

Mount the fogs under the bedrails... There has to be a way if you look long enough.