I replaced my bench seat with some buckets I pulled out of a hyundai scoupe we blew up at the mud races. Carrying a few things home with me, I found that a 5 gallon home depot bucket fit right inbetween the seat and is perfect for resting your arm on. Oh but wait, does the 10 sub fit in the bottom of that bucket? Sure does. Theres my booty-fab addition.
Even used white silicone on a black speaker to get it working again.