For arch clearance,my current 265 75 16 mud terrain have a physical tyre width of 215mm across the tread, and catch slightly at full articulation!
The Kumho KL71 i went for was 245 75 16, this also has a physical tyre width of 214mm across the tread!
The Kumho 265 75 16 was more 230mm across the tread so would have ripped my arches off! :(