Yea, It didn't hold, but that's fixed now. Now I'm currently working on my custom fiberglass sub box. From my initial mesurements, my box will be about 1 cubic foot. Kicker recomends anywhere from 1 ft^3 to 2.4 ft^3 so volume isn't a concern. I had a little excess fabric i couldn't tuck away, so I made that little ledge from the top of the mount ring, this works perfectly in my trunk, and I'm very satisfied with it. Well here's the pics. BTW, that's just felt.
edit:: no more pics