Attached the NACA vent for the reat seat to to the IB bottom skin. Layed out locations for six rivets, drilled holes in the vent and the skin. Removed primer and scuffed the faying surface on the skin. Deburred and dimpled the rivet holes in the skin. Countersunk the holes in the vent housing. Mixed up some leftover proseal and applied it to the faying surface. Back riveted the vent housing in place.