Whats involved with that? If I do it, I want at least the same or better sound. My problem is the sheer size of the sub. That thing is huge. I want to reuse as much of the original parts as possible as well so if replacing just the box works as a plug and play that would seem to be the best solution for me.

 

You're gonna have to get a wiring diagram but it shouldn't be too hard but you will have to splice into the factory wires unless you want to run all new wires. Your call there.

Basically you need to unplug the factory sub box and remove it. If you want space then you're gonna wanna drop to a single 10" or 12" sub (I recommend 12") in a single side mount box to free up the space and a new amp (unless you wanna use factory). Now this is where you're options get screw ball. You can tap into the factory harness to get your preamps and amp turn on/power/ground (if you use a new amp) or you can leave the factory harness alone and run new cables (which I'd recommend) just incase you ever want to put it back in when you sell the car.