1953 and earlier 216/235 engines had one type of rear motor-mounts (and needed a transmission rear-mount, at least on 1/2 ton trucks).

1954 and newer 1/2 ton trucks had a different frame cross member and rear motor mounts, and they did not need a transmission mount for 3 and 4 speed manual transmissions (but needed a transmission mount and frame cross member for the very heavy 4-speed Hydra-Matic transmission).

Tim