Alright so im wallin my car off. building the false floor and so on but question is this. the box walls do they need to be straight? like 90degree angles? or can a box have like 2 45 degree angles? (board would be like 6 inches long) Also the top is wider then the bottom (back seat leaned back) should i just make the back of the box straight up and down? or should i try and get the MOST air space i can? also this is going to be aero ported. (should be the most efficient right? meaning the louder then just normal ported?) thanks!