2006 800xt max tire size

I have a 2006 800xt with a 2 in spacer and am running 27" mudlite xtr which I don't have any issues with, I think the xtr is one of the best all around tire anyone could have. But I always wanted to get outlaws!!! So I'm trying to do some research and seeing how big I can go with out rubbing, is there anyone out there that has they same type/age of bike that had tried installing outlaws and how big have you gone? I wanted to go with 29 but not sure if they would fit with the large lugs. Any useful info is appreciated!!! Thanks