my fi q 15 almost takes up my whole cargo area with my spare in there. 29 x 25 x 16 iirc. 3.8 @ 30 hz. thats right at the window line. i wouldnt even bother with 3 15's unless you plan on keeping the rear seat folded.
For ported on all 3 the box will HAVE to be huge. No if, and or buts about it. I would knock down to 2. Or say F it to any space and wall them bishes //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif