Next you cleco the ribs and skins together and put the assembly into the flap stand/jig. The first set of rivets to buck, is the line of rivets joining the two overlapping skins. I started in the middle and worked my way out to each end. This was pretty straightforward with the tungsten bucking bar. I held it straight up and down inside the flap.
Then I started on riveting the ribs to the skin. I did one rib at a time, starting at the middle again and working my way out to each end alternating sides. I only got a couple ribs done before calling it a day.
