oh yea the rings.
just get the outer dimension of the speaker, and the mounting dimension.
get some 1\2" plywood and cut the inner dimension and the outer dimension + .5 inches. then cut another ring with the outer dimension and then the outer dimension + .5 inches.
glue them together and voila.
use a jigsaw, with a nice sharp new large tooth blade (spend a few dollars on the blade, it will make life a lot easier than a cheap ass blade!)
so in conclusion.
piece 1;
mounting diamater = inner cut
outer diamater + .5 inches added = outer cut
piece 2;
outer diamater = inner cut
outer diamater + .5 inches added = outer cut
you should have two rings now. (always cut the inner cut first, then do the outer cut) get some nice titebond woodglue, and rough up the sides you will be glueing together and then glue em, and clamp em. 24 hours later, sand the poop out of them. and you have flushmount baffles ready for glassing //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
hope that helped.
and if you are just doing doorpods, if you get THICK fleece - its going to only take a few layers of glass, maybe two at most. and if you get really thin stretchy stuff (my favorite) you will need more like 5 layers in most places. im talking between 4 and 7 oz matte.
lemme find a thread i made a while back, and i will show you how i made mine.