Sounds like you've pretty much already got it figured out. But here's what I did last year to get 33's to fit with a 2" BL. The wheels I was using had 4" BS and I eventually upgraded to a wheel with 5.25" BS and still never had any rubbing issues.

http://www.xterraownersclub.com/cgi-local/ultimatebb.cgi?ubb=get_topic;f=37;t=00331 1#000000