I don't know whether I have 28 or 31 spline shafts tbh, mine still have the C clips but I am running 20mm thick rear discs with 1mm clearance either side in the caliper carrier so my shafts are never coming out

My axle came out of a Fox Mustang 5.0GT which was an 84 model I think, it has an LSD but its been sooo long since I looked inside it that I can't remember if its a plated type or not. Can you tell anything externally??