I measured and marked the 5 holes that are located by dimensions rather than match drilling and I drilled them. I also drilled all the 1/8 holes between the 706B doubler and the spar. Finally I drilled the 1/4 hole using the step down bit. I kept everything clecoed and clamped and holes are all aligned. I also drilled the holes for the platenut. I used a #4 bolt to align it and a sheet metal clamp to hole the platenut while I drilled one side. Then I clecoed it and drilled the other side. Then I match drilled the 706B doubler and countersunk the rib and doubler for the flush rivet that will eventually be used.
