Here is a link that describes the Crescent from beginning to end.
http://southern.railfan.net/crescent/cover.html
Here is a link describing the Crescent in 1950 with the consist of the new Stainless Steel, streamlined cars( "The Grand New Train with the Grand Old Name.")
http://streamlinerschedules.co.../crescent195008.html
As for which version of the GG1 to use? Usually, the Tuscan Red was used for passenger service, to match the passenger cars, while DGLE (aka Brunswick Green) was used for freight service.
Hope this helps.