The shells are usually the same, or very similar between the various speeds, 6s-11s. But going to a different freehub will require a compatible freehub in terms of how it mounts to the shell and redishing the wheel to recenter it on the now wider OLD axle width. Also you might want a new axle depending on how much wider the new arrangement is. 4-5mm added width is usually OK, but going from 126-135 really wants a new axle.