Riveted the F-1204D Center Section Aft Bulkhead and the F-1204F Aft Side Bulkhead to the Center Section Assembly. I couldn't use my manual or pneumatic squeezer with the 4-8 and 4-9 rivets because the gap between the rivet sets was not wide enough, I only have one thin rivet set. I used a rivet gun instead which worked well for the most part. I had ordered a thin rivet set but it has not arrived yet.
