Assembled and riveted the HS rear spar halves to the doubler. Then riveted the hinge brackets to the back side of the spar assembly. The 470AD4-5 rivets required the cup set and the 7/16 flush set in the longeron yoke. There were 2 holes that didn't line up properly or were missed during the match drilling of the hinge brackets to the spar. I had to ream them out and then set the rivets wet with primer.
