Well, I ended up putting two Sony Xplod 12's in my trunk powered by a 1000 watt amp and cut out the plastic under the first aid kit. The sound is excellent, however if you need trunk space don't do this. But for a teenager like me, it's perfect, I have just enough room in my trunk for my subs and my golf clubs- that's all I use it for anyway!
Thanks to everyone for your help.