Thanks Joe,
I have looked up that part number and specifications and I'm pretty sure it fits 3/4 through 2 ton AD trucks, and likely more years that I'm not familiar with.
This is the rubber bushing, bearing, and shields to rebuild the original carrier bearing/hanger.
As seen in the shop manual here, and rebuild instructions:
http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0456.htm"propeller shaft bearing support"
Grigg