dana 35 rear question

i have a 96 xj with a dana 35 rear and am looking for a rear locker, i ran across a good deal on a lock-right, but am not sure if my diff is 27 spline. How can i tell? What model # do i need? I have a 242 T.C. if that makes any difference. Thanks, Nick

Yes, it should be 27 spline, they all are.

The only difference is "ABS" or "Non-ABS"