I photographed these Korean-era M43 ambulances at the Yanks Museum and Dubois, Wyoming. The M43 ambulance was built on the Dodge M37 platform.
One of the visual differences between the M43 and the Dodge WC54 Ambulance is the thin shape of the roofline, especially when seen over the rear doors. The WC54 looks bulged in comparison. The M43 also is slab sided, while the WC54 has a ridge of bracing above the rear tires.