The aluminum on the dynamat is pretty thick and can hold a shape if you press it in place with the backing paper still on. So hold it where you want it, just slightly over the edge you are going to cut. Press it to the door so it hold the shape of the edge of the door. Then when you pull it away you can see exactly where you want to cut. Utility knife would be best on a piece of plywood.
---------- Post added at 06:07 PM ---------- Previous post was at 04:16 PM ----------
Here's a couple shots with the monitor in place to get a better idea...
I forgot the Tiger Hair at work so looks like I'll get to the fiberglass and filler tomorrow...Oh well, Pats & Saints on tonight so it's all good!