An interesting side to this question is that the Farmington Branch was laid standard gauge out of Durango using S.G. ten wheelers that were shipped to Durango in pieces.
As I recall there was great urgency in doing this to keep the Santa Fe from poking into that region. I wonder if this machine was used to speed the process of laying trackage?
Great question on this issue. Thanks for bringing it up. I'd never heard of such a critter.
Mike