William Wynne was good enough to provide me with easy instructions in how to mark for the spinner cutouts. Because the Van's spinner is semi-translucent, it is possible to shine a bright light from one side through the other and trace the outline of the light beam. This gave me excellent side-to-side alignment and nearly perfect front-to-back placement. I cross-checked it with measurements taken from the back of the spinner bulkhead to the center of the prop hub opening, and I was at most 1.5mm off from front to rear. Given the fact that the prop blade is bigger as it passes through the spinner (2 inches at its widest) than at the root (1.5 inches), a minor variation in this axis will not even make a difference. Tonight's work time included removing the propellers I so carefully pitched the other night. Oh well. That's the price of progress.I'm ready to cut 2 inch holes in fiberglass
