I do not have specific experience with either of the M-Bs you refer to, however, two things I'd suggest you keep in mind:
1. Before letting the old fluid out, make certain that the fill plug will come out.
2. Make certain to clean the vent on top of the differential. Soaking in parts cleaner and shooting some air into the vent will help get it clean and keep the differential from wearing out prematurely due to the vent being clogged.