PRR's GG1 was a streamlined electric locomotive introduced in the mid-1930s, operating along the US Northeast corridor until the mid-1980s.
In it's heyday, this model was used to pull seven passenger cars from Washington, DC to New York City, with 22 trains a day, travelling at 100 miles per hour. This is not done by Amtrak today, and serves as the best possible argument in favor of the plot of Atlas Shrugged.
Anyway, it's beautiful train and a wonderful example of 1930s industrial design.
Although the GG1 is about 80 feet (25 m) long, it's bilaterally symmetrical allowing for very large models to be made with printers with limited build volume.
The pantograph may be tricky for FDM machines, but some of the more professional machines should be able to do that.