In the del sol i have there is a fire wall between the trunk and the cab. so there is no sound that comes through. i would cut out the fire wall but i'm afraid of doing somthing bad to the rear window guides. So right now i have my 12" subs in truck boxes behind my seat and that just plain sucks because the subs don't have enough air space to sound very good or be very loud.

If any one has put a bumpen system in the trunk and got the sound to come through the firewall could you please tell me how to do it?