Cut a 3" or 4" stick as template and do a quick run down the edge.  Not a big deal.  Accuracy is not important here.

Kim

Kim's absolutely right about the accuracy. In fact, most plans show too many stitch holes. Unless the panels are exceptionally tortured, you actually get a fairer shape with fewer stitches. Fewer stitches let the wood curve more naturally and can avoid humps and bumps and twisting. On my current built I had the stitches no closer than 1 foot, but the average spacing was 4 feet (on an 18 foot boat).

So even if your design calls for 4" spacing (and by all means follow the designer's instructions), the exact positions won't matter.

Laszlo

Thanks again folks! I also sent an email to CLC and they confirmed what you are both saying...anywhere around 5" spacing is plenty and not to be overly worried about the accuracy of the holes. Seems like an extremely important detail but I guess I won't understand until I get there.

Harlan

This was the same issue I had. I contacted CLC and they sent me a layout to drill the holes myself.  This took some extra time but apparently the drilling issue has still not been solved at the shop level.