Countersink Baffle

[lvfive.o]

When making a baffle for a fiberglass enclosure what is the easiest way to make a countersink for the speaker. I have a router on the way and I was looking at rabetting bits but I havent quite figured out how to use one to make a deep enough and wide enough cut to countersink in the speaker. The cut would have to be about 3/8 deep and about 13/16 wide to accomadate the speaker.

Thanks

[bjfish11]

You actually make two rings. They will both have the SAME overall diameter, but the holes cut in the center will be different. The bottom ring will have the inner diameter cut for the mounting diameter of your subs, and the top ring will have an inner diameter of the overall diameter of your subs.
Kinda confusing, hope this helps.