Actually, that's not true.
The NP203 was in use in 1974 on the Ramcharger & Trailduster, with Automatics & Manuals (NP435, NP445, A250, and 727).
In 1975 the 203 replaced the 205 on All Dodge Trucks, Manual and Automatic and was the only transfer case available in W100, 200 & 300 trucks...