Laid top skins onto right wing spar and marked rivet lines along spar flange. Measured and marked off position of rib #1 and clamped rib into position. Had purchased copper tubing-3/16" ODX1/8" ID. Had 1" and 1 1/2" lengths cut. Cleaned up these tubes and used them as drill guides for drilling rib #1 bracket to spar using 1/8" bit as pilot. Found that pilot holes in bracket were on opposite sides of centerline drawn. Drilled one hole to size, 3/16".
