Do you want bass that will make your gut hurt? If so, it's not gonna happen with the small amount of volume behind the seat unless you move it forward. Having said that, I have 4 - 8s in mine, and it will definitely make your eyeballs rattle a little. LOL The box is super easy to build yourself. My cousin and I have built two of them, one for my truck and one for his. We just measured the distance on the bottom and top of the box area, made an angle cut to match, and stair stepped it for the motor and cab vent. For the other cab vent, we just cut a hole in the box and put a piece of MDF on the inside to seal the hole.