Try to stay around the factory wheels' backspacing, which is 5.5". At that a 9" will only stick out an inch more. Go to a 5" b.s. and you've just pushed them out another half inch, (more likely to rub inside the fender at full steering lock, the further out you push them). Don't go too far the other way either, or the tires will rub the steering knuckle/spindle, so maybe 5.75" or so would be the maximum.
Btw, I just got the Toyo MT, but was considering the AT. The salesman said that the casing on the MT is a newer design and they are a lot smoother than the Toyo ATs as they wear, (for the LT sizes). From others' report on the MT they sound better than a lot of MTs for the road. Mine handled great in the rain last night on a very curvy road while driving at a good clip. I had them siped
though, for an extra $60.