Same principal for my permanent P90 template. The fugly black one in the first photo. It's all square edges, just pieced together. looks akward, but it works a treat. Never bothered to even trim down the sides haha but I've used it a number of times as is.

And the tele templates in the same photo, I just printed them out 100% scale and glued onto MDF scrap. Then hogged the majority and filed to the lines.