From what I have observed on the UP's Sunset Route through Arizona, the only thing that was done to the SP, Cotton Belt and Rio Grande engines was to renumber them -- they still have not been repainted and probably won't be. A single white line has been drawn through the Southern Pacific or other road name on the side of the engine, and the new numbers have been stenciled on the side of the cab right under the window, preceded with the letters UP; such as UP 2345. That's still the only thing that has changed after all this time.
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