Not until you model American you don't really know about the theory of "A prototype for everything". Through running there makes anything possible.
Take this: http://www.railpictures.net/viewphoto.php?id=441364&nseq=23
A Mexican unit on Eastern US railways that dont connect to the Mexican network directly. The Ferromex unit is obviously off a BNSF train, but in the mean time Norfolk Southern want to use it