NOPE, these sets of holes are horizontal and are directly opposite each other suggesting that a bracket once existed there maybe spanning the cargo space, like a closet hanger bar.
These holes are well done suggestintg that it may be factory but maybe not. It's obviously no big deal since you guys seem unfamiliar with it. Thanks for the pictures Marty those are 2 spectacular trucks. I'll send you some pics of mine in progress.


All the best, Ted