Scott,
I didn't know if you wanted to use a spacer between the rears or not, but here is texs4x4's truck. They are a 305/85r16 which equal a 36x10.5. Probably would need a 1.5" to a 2" spacer. Should be the biggest size for a 2nd gen and also close the the 255/70s you have now.
hey thanks for posting the pic, ive been killing myself trying to find pictures of the 2nd gen with stock rims and big tires as well as 17, and 19.5 with all terrains on,dont get me wrong i love the 22.5 with spikes on my truck but, if it wernt for the looks and the lower r's(4:10"s) i think i would have nver got them. kinda doubting myself and looking for a possible alt route to go . i def like the looks of his truck, looks sharp, as well as he would be able to yank somepeople out of the mud where as me i just have to stand by the road .lol