I decided to quit messing around and ordered a Cerwin-Vega powered sub for under the driver seat. I don't want to spend $600 for the JL Stealthbox and then more for an amp and end up with a carpeted center seat that my dog would have messed up in no time, or mess with building something. I don't need super bass in this truck, just something better than what it has. The CV has the best reviews on Amazon for a powered sub that fits under my seat. For less than $200 I figure it's worth a shot. It is a 10" with 200 watts RMS and freq response of 30-150 hz which is better than most of them and it has an aluminum chassis and remote level control.