my 96 regal back seats ******.i took the seats out and there was a metal brace that had one spot that was like 14x14 .u might b able to cut the rear deck if u wana do that. or if u have that same metal be hind your seat like i did u can cut it away. oh yea if u want to leave the seats then take out the rear speakers for better air flow . 96 regal custom series 2 ftl
i had 2 12s sealed, off of like 400rms at 2 ohms. then some bs box that was ported for 2 12s. 30w15x20 ish. u might have to cut the rear away. or u can do alot of 8s . sell off your 15 get a few subs to make up for the cone area . u wont need a tall box for some 8s .