Good idea Jay, lets get rid of those fugly flaps

Stereo's in with some cheap Jaycar speakers.... Always thought Jaycar speakers were good but these are absolute crap. Thinking about making a fiberglass sealed enclosure for an 8inch or 10inch sub to fit under the passenger seat. Only problem with it (apart from the cost of making a fiberglass box) is that my amp (1200wrms @ 1ohm, hehe) wont fit under the drivers seat so it would have to go behind the passenger seat with the seat slid forward two inches. I haven't had many passengers but most struggle to fit in with the seat all the way back so its not practical at all. But the bass would be insane in that little cabin.
I also got sick of the chain noise on the body so wrapped with a plastic flex tube.

Anybody know how much resin I would need to make a small fiberglass sub box that's molded to the floor and around the seat mounts so its as bigger volume as possible?