I used a 36" long piece of 90-degree angle steel meant for hanging garage door openers. $9 at HD and has holes for easy screw-mounting when the clamps won't reach. Made a workable fence for both the circular saw and the router.
I like the idea of using the templates, and if everything was glued all at once, it might be easy enough to make any little adjustments or deal with slight warps. You'd have to be quick though. Not sure I'm brave enough for that.