8 3/4 rear end LSD identification

Surprised it did not have the same issue I had.

mine was a 742 case changed from 4.56 to 3.55.

Pinion Depth issues for me! 741/742 used Dana/Spicer 4 pinion clutch units in the center. They were slightly smaller in circumference! Had swapped my center to the 489 style SG at some point, Long story! I had to shave the pinion face to keep from hitting the center and get correct gear mesh alignment.

It does not look like a standard 489 type center to me either in the pic. I suspect an aftermarket center.

Doctor Diff can shed some light on these issues!