For some reason I was thinking I needed to wait till later to drill the rear spar. After revising my punch list for my next steps I realized that I can go ahead and drill it now. I just can't rivet the rear spar at the flap area until I'm ready for the skin stiffeners.
I drilled the rear spar. I didn't drill the aileron pocket rib locations yet. I'll mark the skins and then remove the skins and drill. I unclecoed the top panels and pulled back the panels to do all the back drilling. Andrea and I back drilled the main fuel tank and aux fuel tank bay cover panels. For the main tank panel we back drilled the sides then I positioned the panel aft of that area and drilled the overlapping panels at the same time.
