I have seen a few pictures of people that have made a bandpass enclosure with the port firing into the cabin though a hole that was cut into the two steel plates behind the back seat. Has anyone done this, or has heard how this setup sounds? As of now, I have 2 - 12"MB Quart discus subs in a fiberglass box where the back seat should be. I want my back seats back, so i'm looking for options that will still put out the bass.