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I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.
When I rode from Penn Station to Easton, PA, in 1947 (15 years old), the consist had modernized heavyweight cars, mostly if not all with "railroad roofs," not arch roofs, but with fluorescent light interiors and reclining seats. All were painted "Cornell Red," the color of Cornell College's banners. There were heavyweight Pullmans as well, also painted Cornell Red. This is a color near scarlet, probably hard to tell the difference. Lightweights may have come later.
Possibly office car LV 353 at Steamtown has been restored to this color.
Thank you very much for your reply! Do you remember what color of fluorescent lights Class I railroads were used during 40s - 50s (PRR, NYC, Milwaukee road...etc) ?
Jones 3D Modeling Club https://www.youtube.com/Jones3DModelingClub
Supposedly white, but actually bluish like most at the time.