Countersunk left aileron trailing edge , dimpled left aileron trailing edge and top and bottom skins. Dimpled right aileron top and bottom skins for ribs and stiffeners. Riveted right aileron top and bottom ribs and stiffeners. Drilled counterbalance to nose ribs and skin. Attached counterbalance to nose ribs. Assembled right aileron and fitted, marked, and drilled trailing edge piece. Countersunk trailing edge piece.