8.75 Axle - 741 / 742 / 489

Just wondering why you had to toss a cone style, I have had real good luck with them for the past 30 years, sometimes shimming and machining is needed, but not often.
I have run clutch styles also with minor issues.

Most of the time excessive wear is caused by the wrong fluid or additives which causes the cones/clutches to slip and basically overheat, wear and abuse does take it toll but any rear will eventually get tired.

I've re-machined a few of them too with good success but this one was absolutely trashed. The housing where the cones rode had big grooves in it and the cross pin for the spider gears was wollered out real bad (I'm talking 1/4" gap, LOL). The spider gears and ring and pinion were fine. For that reason my guess is someone ran it with no limited slip additive for a long time. Not sure why the cross pin was wollered out but I've seen 3 of them that way.