Anybody ever built a downfiring sub enclosure for a supercab? Or does anyone have a link to a site that has one that I can reference? Otherwise if anyone has built a box for a single 12 inch sub for under the back seat of a supercab that would be awesome. I picked up a Kicker CVT 12 for $50 the other day and a 760 watt Pioneer Amp for another $50. Any input would be awesome.