For the people saying it's way too big, have you actually heard L7's in a box that size? If you have and you can really tell its too big then I wouldn't do it.
I made a 2.75 @ 33 hz box for (1) type R 12" sub and people said it was too big, but after hearing close to the same setup, but in a smaller 1.80 @ 34hz I actually liked the sound and output much more of the larger box. Thats just my opinion.