Well, this should give us some idea of wheel & tire fitments. Seems 8.5 will work and some are squeezin' 255's at the rear w/o rubbing. Others are going 235 all around.
Hope this is ok to link:
http://www.babybmw.net/forum/viewtopic.php?t=6509 &
http://www.babybmw.net/forum/viewtopic.php?t=6402