After carefully measuring, re-measuring, triple checking, my drill hit a knot or something dense in the mounting blocks and slid off-center. The wing now is now out of alignment by a full 0.5 inch!

My fix will be to open the two holes in the wing to allow for enough “travel” so that I can re-align the wing. Once properly re-aligned, I’ll epoxy two “washers” over the widened holes. Washers wil be made from scrap ply. See pics below. Please comment on my fix or suggest others, thanks.