B&O Royal Blue:
Thomas Underwood Coll B&O304 by John W. Barriger III National Railroad Library, on Flickr
After there was more C&O corporate influence (late '60s) there seemed to be more "Enchantment Blue" prevalent.
Thomas Underwood Coll B&O416 by John W. Barriger III National Railroad Library, on Flickr
Just my unscientific observation.
Good Luck, Ed
I have seen pictures of black and white lettered bo diesels from this dera . Correct or notthe cars are so what's correct.