Positioned the bottom skin on the right wing. There was a slight interference between the skin and flap/aileron attaching bracket. It was filed to enlarge. After the skin and the inspection port brackets were clecoed the skin and the front spar were matched drilled, dimpled, countersunk, deburred and finally riveted. The rest of the rivets were installed leaving the last 4 near the rear spar only clecoed. This is done so that the skin and rear spar can be matched drilled. Note: I was not at 100% so Chris did most of the work.