I cleco'd the spar onto the flap after doing a good check to be sure all rivets were set on the inside of the flap. Pulled rivets on the lower side of the spar were easily accessible with my puller, but I needed the "wedge" to allow the puller to be at an angle to get the top rivets. Could not find any left-over trailing edge wedge material to make one as indicated in the plans, so I used bar stock and made my own angle on the belt sander (See image1). Alternated bottom and top rivets from the center out, then did the rivets on the end ribs.
Used the squeezer on the bottom of the spar to set rivets for the skin/spar/hinge. Started at the center and set every other rivet. Turned the flap around in the stand and used the gun and tungsten bucking bar to set the top skin rivets. Went from center out, setting every other rivet, then went back and filled in the rest. Turned the flap again and filled in the rest of the bottom rivets.