Dave Ross ground off more material off a set of vice grips. Was then able to squeeze -3.5 rivets properly at the end of 404 ribs. Also tried to pull sides of rudder horn brace up to flanges of 404 rib and skin. Brace material is thicker than flanges and the skin and so the flanges and skin were being pulled in to the brace. Gap is ~1/8" wide between brace and flange. Possible alternative is to place spacers in the gaps.
