That brass fitting (block) is different, for different years/models truck.
A truck with manual transmission has a different fitting/block than the one used on a truck with a hydra-matic transmission.
Most likely, there were different blocks on some earlier trucks?
Jim Carter & Chevs of the 40s & The Filling Station do not list any.
Maybe someone knows another vendor that has it/them.
What type of transmission on your truck?
