Sweet box! Allstar is a great guy to deal with. He posted that he is able to do this and was shut down (non-vendor) so I sent him a PM with my design. I got my box and its perfect!
A RD Audio Heavyweight GP 12" will be paired up with this 3.5 @ 30hz box with about 2200 watts.
Again, a great guy to deal with if you need something. Wouldnt hesitate to deal with again.