Clamped, match-drilled and clecoed the flap ribs to the spars. Made the shims for the aft ends of the ribs. Match-drilled the ribs to the bottom skins. Clecoed the top skins to the spars and reamed the holes. Match-drilled the ribs to the top skins. Marked the ribs for position, disassembled the flaps and de-burred the parts.