Identity Confusion?

The RS1 by the American Locomotive Company was the first in a long line of Road Switchers introduced by the company in early 1941. The RS36 was the final model that Alco sold in 1963. The picture on the front of this post card is of an RS2. The RS2 started as a 1,500 horsepower locomotive but was increased to 1,600 later in the production line. Our friends at Wikipedia (https://en.wikipedia.org/wiki/ALCO_RS-2) tell us this about the development of the RS2 locomotive: “The RS-2 was a further development of the road switcher concept inaugurated with the RS-1. Externally, the RS-2 bodywork was more rounded. A more significant change was the switch from the RS-1's ALCO 539T engine to the ALCO 244, adding horsepower to better handle heavy road service. The new engine was a turbocharged four-stroke V12 diesel engine with a 9 in × 10+1⁄2 in (229 mm × 267 mm) bore and stroke developing 1,500 (later 1,600) hp at 1,000 rpm. Compared to the 539, it had a smaller cylinder and higher cylinder speed. Production of the RS-2 was delayed several months while ALCO worked out the new four-pipe divided low-rise manifold for the GE constant-pressure RD-1 turbocharger. The 244 engine was not a reliable design, however, and was replaced in less than ten years by the ALCO 251 engine.” 377 RS2 models were manufactured from 1946 to 1950. The Lehigh Valley Railroad ordered five RS2 locomotives for their roster. The records that I could find online tell us that the locomotives were numbered from 210 to 214. This picture shows one numbered as 217??? The picture was taken in the yard at Buffalo, New York in 1976; perhaps there were some changes made that warranted a new number for this locomotive. I wrote some information about the Lehigh Valley Railroad in the November 5, 2025, post; you can go back and read about some of its history there. Here is the back of the post card.