Drilled, debured, dimpled and edge finished L & R aft fuselage cover plates. Removed tabs from F-879-1 seat ramp. Drilled all #40 holes of L & R F-880B seat ramp ribs and F-880A-1 forward seat ramp. Deburred all holes and edges of L & R F-880B seat ramp ribs, F-880A-1 forward seat ramp, and F-879-1 seat ramp. Dimpled #40 holes in seat ramp ribs and seat ramp.