From those choices: two 216 carburetors (1951 would be Rochesters - many people would recommend earlier Carters). You still might have "too much" carburetion. Maybe first-hand experience or/and expert advice (Carbking, etc) will be posted.
If you are having lines made to order, you should mock-up your intake, carburetors, and fuel pump (to match the angle on/to the fuel pump and on/to the carburetor, and the distance from the fuel pump to the nearer carburetor) .
