I am getting 2 12s and ive got little space for them. I need instructions on how to build a box (preferably a wedge). As far as depth goes ive got about 11 in. on the bottom and about 7 in toward the top. It can be as wide as 5 ft . Heightwise it can go about 20 in. Mounting depth is 5 9/16". Volume is 1-1/4 Cft. Thanks in advance.