Swapdonkeys

Hey guys first of all thanks for having me here! I messed up my user name it was meant to be Swampdonkeys after a 4x4 club I had. Anyways what I have is a 2003 GMC 2500HD Ext Cab and I am trying to put a 10 W7 under the back seat! This is hard to because of the size of the sub and air space, I do need to keep the back seat and I cant point the sub down or up into the seat do to excursion. So what is was thinking is if I put the sub facing the back drivers door and a port facing out the back towards the back window, to do this I think I will need to raise my back seat 3" not to mention the box is going to be interesting to build. I have seen the stealth box's JL make but they are for a W6 and insufficient air space for a W7 but the interesting thing I seen is they point the sub to the back window and the port. I did not measure 10" + at the back of the seat, Maybe I need to double check. But what are your guys thoughts on how I can get this monster into the truck? Has anyone tried this or dose anyone have a box blueprint?