Removed bad rivets and used a can of cleco's to add some weight and hold part for offset riveting. Successfully replaced bad rivets.
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. Alternated bottom and top rivets from the center out, then did the rivets on the end ribs.
