Honestly, thats exactly what I was thinking. The recomended ported box size is 5 cubes though, and I didnt want to screw anything up. Here are some pics of what I have so far, and the trunk. It doesnt look all that small but the depth from the back to the little bump behind the seats is only like 24 inches, and its only 15 inches high under the hatch so having the sub fire backwards is impossible. From the top of the back seats, its about 16 inches to the back hatch at 20 inches high. The most narrow part of the box is about 22 inches and the widest part at the back is 46.
Any suggestions would really be appreciated. Haha I dont want to put a ton of time and effort into this box and then have it sound like shit. Thanks guyss