Hey all,
The jig was a 'hail mary' on my part but it did work well - I also tend to over-engineer so keep that in mind

jimmy2x2x - I secured the jig on my deck outside. Cutting the arc was a piece of cake with the jig and, as
javeryh suggested, I then used this piece as a template to cut several other 'test' panels. To be honest, my
template required some minor tweaking (for squareness) even after using the jig, but once complete it can
be re-used any number of times to get a perfect blank.
I found that the problem wasn't so much drawing the arc as cutting it. However, use the suggestions provided here to get the curve you want and I'll bet you can get darn good results by rough-cutting with a jig-saw
and sanding to the finished curve line. Given the size of the control panel, and the likelihood that it will be finished in t-molding, hand-finishing would be a practical option...that is if building a monster jig you'll only use once isn't an attractive option

Breaker.