Found time to take photos for you!
I choose to drill threw, from the bottom, both the bed rail and the bar. I went threw holes that were already in the bed rail.
As mentioned before, I couldnt get washers inbetween the underside of the rail, and the bed wall. So I cut, drilled, and painted a steel plate to fit and distribute the weight just as a washer would.
As you can see, I do have some bolt cutting to do! When I get the time I will (they are not the only ones that need cutting and painting)
I completely ditched the expansion plug, it is useless!! It did not hold worth anything at all. However this
method has resulted in my being able to grab the bar and shake the truck back and forth without the slightest movement on the bar.
Ive had the bar on the truck for about 8 months now, not a single problem.
Hope this helps clarify my method for you