Some more photos of what was described on the previous page.
Picture 1 shows the already-in-place holes on the opposite face of the spar web. The spacers are on the other face. So with some wood backing up the spacers (so they don't pop off when drill pressure is applied), I drill pilot holes through the spacers using these existing holes.
Picture 2 shows the spacers stacked after drilling.
Picture 3 shows all the spacers drilled and deburred, ready to start laying out the nose ribs.
Drilling from opposite face of spar, through spacers.