Someone that also said about putting the speakers in the door is right. you can put huge speakers in the doors BUT they have to go in the back (read toward the rear seat) part of the door. So when you close the door the speaker actually is just behind or even with the back of the front seat.
Actually mine are in the front lower corners. http://mmb.maverick.to/attachment.php?attachmentid=1697&d=1058480515