Just checked, the 54 Plymouth and the 54 Pontiac. Both cars had locks on both sides.
The 46, 48 and 1950 2-Tons had locks only on the passenger side.

Don

1967 GMC 9500 Fire Ladder Truck
"The Flag Pole"
In the Stovebolt Gallery
1946 2-Ton grain truck
1946 3/4-ton pickup,
1953 1-ton pickup
1957 1-ton flatbed dually,
1954 Pontiac Straight Eight
Of all the things I've lost in my life, I miss my mind the most!