I routed the excess gussets off with a flush trim router on the top of the fuselage. I glued the gussets to the top of the fuselage, attaching them with T-88 and small stainless steel brads. I cut out and glued the filler strips to the bottom of the fuselage. I also added a spruce wedge between the top of the floor piece and the diagonal brace that crosses under the rear seat back.