Try the Nissan section on Outerlimits4x4.com. There is a post in that section or in one of the Nissan bibles which gives all the difs Nissan produced. If you don't find it, then post a question in the Nissan forum (make sure you told them you searched first). The guys there are pretty good but there are a few dorks who are just hanging around to flame people. I can tell you that the centre of a Pathfinder rear dif is the same as the front dif on a Nissan Safari. Sorry I can't help you more.
You will be looking at a Nissan H233B LSD Dif with a 31 spline count & 32mm axle dia. Generally, these are a 4.111 ratio. I am considering the centre for my front dif on the Safari. Not sure how wide the axle is hub to hub on a Pathy. You may be looking at cutting it.