After metal trimmed per Alpine install instructions.

Details	:	About 2/3 of the diameter of the circle needed to be trimmed. All I used was a Dremel with some "heavy duty cut off wheels". First side took a while and a few cut off disks. Second side took about 25 min and only 2 discs. I painted some primer on the cut edge, and put some vblock on the outer door panel. I also used some to make a "gasket" around the hole and under the adaptor.