Mounting Universal tracks to Bed Side Tops

Somewhat Newb question but here goes.

I'm running a Bakflip F1 which leaves what looks like plenty of room on the tops of the bed sides to mount a permanent track system for cross bar towers (in this case i'm looking at Front Runner rails and crossbars for max versatility and load rating for a possible tent down the line).

Now some questions. How does one go about affixing the base rail to the top of the bed? I'm too chicken right now to pry the plastic cover off to see what is under there. I assume there are two holes at either end i could make a bracket for but do i drill the middle?

Also I've seen so quick release sliding rail bases, but no real tower for that sort of thing. Any thoughts on that end?

My ultimate goal is versatility. most of the time the cross bars and towers will be pushed all the way forward to allow the cover to open the first 2 folds. Even then with the Front runner stuff you get a pretty big shelf that I can tie down coolers and hard cases to if necessary.

Thoughts?