Crew cab owners: What subwoofer box are you using?

[arrover]

I'd like to put a 10" or 12" sub in my crew cab but it is incredibly tight behind the rear seat. What are you guys running? I've built sub enclosures before but I was hoping to avoid having to do that. Width is pretty unlimited. The max height is 15". The depth at the bottom of the box is 6.5" max and the top max is 3". I've looked at a ton of boxes online and so far none of them are shallow enough to fit.