I think we are talking about different things, I am talking about the ammount of friction between the plates inside the diff as some diffs allow you to swap them around to adjust the locking force point of the diff.
I think you are worried about the ammount of play you will have between the 2 support bearings of the diff, the tapered roller bearings at each end of it. I just dry fitted it then once the casing was tightened measured the end to end play by lifting the diff.