Clamped rear wing spar in place and check squareness of the boxes.
Alligned pilot hole line on rib and clamped tight both top and fore and aft, drilled through rib and silver clecoed. Did the same with the bottom hole then drilled both middle holes for the silver clecoes.
Added the rear root doubler and hinge doubler and opend up half the holes and installed copper clecoes. Removed the silver clecoes and opened the holes up to #30 then opened them up to #20. Added the black clecoes and removed the copper clecoes and opened the rest of the holes to #20 for the A5 rivets along the eitire rear wing spar.