Riveted LH HS front spar to skin between main ribs #4 and #5. Riveted the #5 main rib to spar and skin. Middle 1/8" rivet on the rib squoze out between the faying surfaces. Drilled out and hole got distorted...couldn't squeeze a second AD-4-4 rivet cleanly at all...arggh. Drilled out with #21 to get smooth edges and filled the hole with an LP-4-3 blind rivet. I will need to put in two rivet holes either side of the middle hole for structure integrity, I think.