I was not aware the Southern ever painted their Mountain class locomotives in the passenger green & gold colors.
me neither, but here is some evidence
Evidence? I'd say that is proof!
Those Lionel Southern Ts-1s sure look nice. I wasn't even aware that Lionel had done a USRA light Mountain until I was researching this thread. They do seem to be available on ebay with some regularity and would be good candidates for an electronics upgrade.