1. Drilled counterbalance tube for left aileron 2. Temporarily riveted left counterbalance tube to left aileron ribs. 3. Clecoed aileron leading edge skin to ribs and aileron spar. 4. Cut out and polished all 28 aileron stiffners 5. Match drilled all 28 aileron stiffners to top and bottom skins of both ailerons. 4. Dimpled all 278 aileron stiffners.