I am going to rebuild my box tonight and will post pictures by this weekend. Currently I have two separate boxes, but think I am going to connect them to make the box heavier.

 

Sorry the photos took so long...

I am very happy with how it turned out.

Pictures suck, but you get the idea...

 

8 inch drivers? And did you end up connecting the boxes?

 

Actually they are JL Audio 6W3s (6.5") I don't know if you could get 8" in there... The faces are only 7.5". It would be really tight. Not only height of the sub, but the box would be more difficult to build to squeeze the needed air space. The JLs only require .15 cubic feet each.

Yes I did end up connecting the boxes together. If I get a chance tonight I will pull up the back seat so you can see it. Nothing fancy, I just did it thinking that the boxes would have a less chance of turning since it was a large box. I built the whole box with one sheet of 3/4" 24"x48" MDF, so it only cost me $10 for the box...

I am more than happy with it. You can defintely hear and feel the subs. I am pushing them with only 300 watts (which is their limit) with an Alpine V70...

 

I do car audio install for a living and if you get a slim sub and can have enough room for a box with the right specifications for the sub (you don't need that much depth with a slim sub) you can have it up firing into the seat. That's what they are made for. You can put a 12" under there if you don't think u will be putting the seat down! Look at the MTX thunderform, you won't find one for a jeep but that doesn't mean it's impossible!