It's true! I found A 1930's NYC Hudson found in a museum.
Of course, it's a 3/4" scale model. It is in the New-York Historical Society, 170 Central Park West, New York City.
Charles Lamar, between 1933 and 1939 built this model from plans supplied by the New York Central Railroad. He made the wood patterns for the parts, had them cast, then machined the pieces to tolerances of 1,000th of an inch. The model and the case it's in was on exhibit in the Railroad Building at the 1939 World's Fair.
You can read more about it, including reference of the tender as a freight car, here. http://www.nyhistory.org/node/30925
There is also a mind-blowing exhibit of 19th century Marklin and german toy train manufacturers from the Jerni collection. Strict no photo rule so no pics.