If both carburetors came off a 216 engine, they should both "fit" onto the intake manifold. The throttle/choke linkages should be the same. I think the car and truck air cleaners would be different but either will work. (wait to hear from someone else on these matters)

Some (many) people like the Carter over the Rochester.

Carter carburetors used on cars in 1948.

Carter carburetors used on trucks in 1948.

Carter carburetor used on cars in 1949.

Carter carburetors used on trucks in 1949.

Rochester carburetor on cars in 1950.

The model B Rochester was introduced to trucks in 1950.

Tim
1954Advance-Design.com
1954 3106 Carryall Suburban
1954 3104 5-window pickup w/Hydra-Matic
The 216 and early 235 engines are not "splash oilers" -- this is a splash oiler.