my oppinion is get some solobaric subs which dont require a very big box 2 10's or 12's should be good they make special boxes just for trucks.....it should fit right behind the seat.. what im gonna do is i have a 93 ranger x cab im gonna build boxes right into the sides behind the rear fold down seats.. i wont be ablr to fold them back up but who cares its better than havin a big bulky box like i have now and not be able to fit anyone in the back......