Id get rid of the 15, and run a pair of 12s,beef up the electrical, and get good mono amp of 1k-2k at 1ohm@100db,or build the box inside the trunk for the 15 and get some cu ft in there, and start deadning the trunk/doors/floors/and roof as well as some plywood or MDF the roof up,and take the back seat out,use the trunk space for the box build for the subs..subs forward/port forward..You want spl, but you have a tin canned body to work with that isnt sealed off/enclosed.Give that 15 some cu ft it needs to perform..or get a pair of SSD FI 1k-1.5k rms-12s in which would more than likely be much better in my opinion,and an American Bass VLF 100.1 and throw in there.That will get r done,or throw that amp on the 15, and do the cu ft needed for that 15 right
