Gathered final batch of part to be primed - wing attach skins and ribs, lower cowl closeout. Edge prepped parts, trial fit of skins showed that I had reversed the upper forward attach flanges many months ago. Drilled out 12 rivets, swapped left and right sides and re-riveted. Holes in wing attach skins line up correctly now. Cut flap pushrods to length and cleaned threads. Installed shoulder harness leads.