In 1952, the handle changed from turn-down to push-button. The lock was in the button on the passenger side (as in previous years).
Don't know about '52 & '53, but in 1954 there were factory options, #395, that included keyed locks in the push buttons on both doors. The locks were keyed to match the ignition key and the lock on the dispatch box (glove compartment). In addition, another #395 factory option was a matching-key lock for the side-mounted spare wheel (Has anyone seen one of these locks? Please post a picture).
The lock on the rear door of Panel and Carryall Suburban models was keyed to match the ignition key (all years had a turn-down handle with lock in the door, similar to '47.5-'51 driver-compartment passenger-side door lock).
Tim
