Offroad-Express

Does anyone no if a Jen 2 Pajero and a challenger rear diff are the same they both look like they have 9 1/2" heads?

Yes although I think they changed them as well from the 9 inch to the 9.5 inch later in their life, so just need to check. Easiest way is to count the bolts holding the diff head into the housing, 10 = 9 inch, 12 = 9.5 inch.