building a box for two 15 DC LVL4 15's, using aero ports.should i do subs up port's to the rear,or should i fire the subs to the rear and the ports to the drivers side fire wall?subs are going into a 07 impala, the seats don't fold down.just wondering wich way would give me better output. normaly i would just fire everything back twords the trunk lid but not enough room.was also thinking subs up ports up,thats the way i had it in my last car and it sounded great, but the seats in that car folded down not sure that it would sound as good in this one.