building a box for 05 pathfinder

Hello all . I am new to the forum. I am looking into putting in a complete system in my truck. My only issue is that I use the back of the truck to load stuff.  So with that said here is what I am doing .. I want to make my own box custom so that it fits in with mt third row up.  The seats don't sit striaght up so here is what I am thinking and want to know if this will work and sound ok.

I am going to use 2 10" sub's. I am looking at the pyramid pwrd10a. I am not looking for compition sound just good sound. I am thinking of a sealed enclosure with the face of the subs facing out. The design I am thinking look something like this :

The measurements are as follows.  15" H 44" W the top ledge will be 6" w 13" D not the trick here is to fit the back panel the sits against the back seat will have to angle some.  When I measured the space I have 47" W  16" h  as for depth at the bottom of the seat to the hatch I have 17" and narrows out at the top to about 14" so I am not sure if this is confuseing and I hope I explained it ok ..

What I would like to know if I make this box and BTW the top and face are going to be plexi glass will it sound ok?  

Sorry the picture came out wrong

As for how much space I want to give up .. I would like to keep it so That I can have my third row up

when I want and still have the box back there. So I guess as little as possible. If I have to just go with one sub

to keep it smaller and still have good bass that is fine as well. What I am looking for is something that sounds good and still has good bass.

I am not looking to rock windows.