I continued work on the rear wing spar.
The holes on the spar top flange were dimpled.
The plans say the holes on the outer reinforcement plate should be machine countersunk, but I decided to just dimple the holes. Dimpling avoids a sharp edge around the hole.
I primed the parts. I went to Harbor Freight to buy a new spray gun because my old gun was always getting clogged. In the future I need to soak the nozzle in acetone after each use.
I cleccoed all the reinforcement doublers to the spar. 
I riveted the inner stiffener to the spar. The tape covers the holes that should not be riveted at this time.
