This should be stickied.
http://www.japanparts.com/images/ImageFromDB.php?base=1&no=11153
It has been a while since I have been on, and I have scanned through the posts and have not seen this posted anywhere, and if it has been, then I appoligize.
I have found a site that sells a double din dash kit with dual zone A/C.
http://www.japanparts.com/db/parts_detail.php (if this doesn't work use next link)
Half way down the page, part number: 107-209-006, Description: AV PANEL SET
http://www.japanparts.com/db/partslist.php?dealer=1&car=7&middle=2&small=13
I have not tried this, however it does look tempting. They offer bother the single and dual zone climate control.
Enjoy.