Not sure if this will help but these are the pieces off a 1946 half ton that I just cleaned and blasted for a bolter. I suspect the two halves that go around the rear housing are held by two screws that go in from the "top" and screw into the bottoms.
Does this help....

http://i140.photobucket.com/albums/r19/LutherParris/Spare%20Parts/46%20rear%20end%20parts%20001.jpg


1937 Chevy Pickup
In the Gallery
1952 Chevy Panel
In the Gallery
More photos
1950 Chevy Coupe
Pictures!

I'd rather walk and carry a Chevy hub cap than ride in a Ferd.
I can explain it to you, but I can't understand it for you smile