I riveted the upper surface inboard aft skin and stiffener, and used a squeezer to rivet the inboard rivet line, as well as drilled, dimpled and deburred nutplate holes, and riveted the nutplates into place. In difficult situations, the screw and or rivet holes can be countersunk, rather than dimpled, and Cherry nutplate 3/32 x 100 deg pop rivets can be used.
