I dont know the gmc series. its ebay. but here is a picture of the hub.
https://picasaweb.google.com/118219121658359708127/Gmhub#5993725669784133938

if you want to refer to my truck by its designation, its here. I havent had any issues so far referring to it as a 1946 2 ton.
https://picasaweb.google.com/118219121658359708127/Truck1#5753246340398902002