Match-drilled rear seat hinge and fabricate skin spacer for underneath hinge. Drilled all hinge rivet holes to #30. Final drilled all #40 holes in floor skins and stiffeners. Deburred all holes. Dimpled all #40 holes in floor skins, stiffeners and foot well components. Riveted aft control mount nut plates to inboard seat rib angles, but not to floor skins (matching QB installation of forward nut plates), Mocked up assembly of as many interior components as possible.