ok i got a 07 silverado ext cab. the back seats have been removed and built a sold base so that my new box can sit flat on, but i cant seem to figure out what box design to go with. i have 4 kicker cvx 12"s there in seperate boxes now and i hit a 144.5 at the rear view mirror at my last cometition i enterd, but ive changed amps since then too so i should be louder. ive got 1 power acoustik a300db and gettin another one asap. 2 of the subs are firein forward and the top 2 or facein the roof. so if yall could steer me in the right directin i would really appreciate it.