I would like to think this train would normally have had mostly if not all lightweight equipment from the participating railroads in the consist.. When Diesels became the norm, I believe the practice was for locomotives of each of the railroads to run through the entire route Chicago to Florida.. Have seen Photos of Atlantic Coast Line power on this train in Chicago.
Since the Chicago-Floida service was a sort of Seasonal business demand, that Fleet of Modernism Observation might have wound up on a Chicago -New York City train during the warmer months.
If you can like to see some photos here of cars in your consist
