Just installed Zenclusore's sealed S-type sub box built just for the Z...it's great! I'm running 1 Kicker solobaric L5 and love the sound.

here's a full write up:
https://my350z.com/forum/audio-builds/236698-installed-zenclosure-s-new-s-type-sub-box.html

if you guys are interested in checking it out before you buy one from him, let me know.

-Peter