Campy,
That's a great set of instructions for marking a cowl. I used the cardboard for several, but now I've found that if you use clear Mylar, instead of cardboard, it's easier to mark the openings for the carb and exhaust. I use the cheap report folders, or whatever they're called, from office supply stores for the clear plastic. I found it much easier to locate carb adjusting screws this way.

Nashcat