Interesting, I wonder if they were a clutch-based limited slip design? It'd be fun to find one...[/quote]

No clutches, built like this (have one in my newer K2500)
https://www.randysworldwide.com/product/yglgm14t-30/


BC
1960 Chevy C10 driver 261 T5 4.10 dana 44 power loc
1949 GMC 250 project in waiting
1960 C60 pasture art
Retired GM dealer tech. 1980 - 2022