I am trying to put Subwoofer into my 2001 GMC Sierra 1500 Extended Cab in the Back seat. I still want the back seat there but instead of having space for 5 people I was thinking about taking the middle section seat of the back out and getting to single seaters on both sides and was wondering if it could fit and work. This is what I was thinking of.
Subwoofer I want to put inside
Soundqubed HDS312 -
http://www.soundqubed.com/HDS312_p_227.htmlAmplifier -
Soundqubed - Q1.1200 -
http://www.soundqubed.com/Q1-1200D-Amplifier_p_30.html
Get singles on each side (is there a place I can even buy single back seats?)

Sit this upright in the middle of the truck in the backseat.
If someone can link me to some backseats for a 2001-2006 GMC Sierra / Chevy Silverado Leather back seats that would be great that are singles or go on each side. Do they make seats for each sit or is it only one certain side?
Would the box even fit between the sides and would it hit hard enough to even fit in there well? I seen someone else pull it off but its a completely different setup and wondering how he got the seats.

Let me know what you guys think. Also should I get a 2 Ohm coil or a 4 Ohm coil?
Also would I need a custom box for this or should I get one premade?