With Gayle's help, the 18 rivets that join the three center bulkheads around the curve of the fuselage at the bottom were completed. Those rivets were tough, and Gayle did a great job bucking them. I continued with the side skins starting from the tail-cone section forward. It's a bit slow-going, but the tail-cone area is riveted up to the F-786B J-channel stringer.