With spar assembled with spacer bars in place, redrilled offending holes at each end of bars 1, 3, & 4, using 1/8" bit. Was then able to insert rivets somewhat easily. Disassembled spar. Cleaned ends of bars with enamel cleaner. Primed ends of bars with spray primer. Reassembled spar doubler, spacer bars, flange strips 606B & A, and spar with screws. Used 3X rivet gun and bar and riveted spar together. Flattened heads on a few rivets. Cut down 1/2 length all 470-4-11 rivets, to make them proper length.
