I'd forgotten the TA had those not-quite-AAR-B trucks. That makes it seem a logical possibility. But then, the dual engines and the existence of a B-unit suggest the E-series... I'd have to concur with the "hybrid" toy idea.
Check out http://urbaneagle.com/data/RRdieselchrono.html It only goes to 1989, but that's more than good enough to show the spread of early diesels. Many accidentally repeated lines, and many inconsistencies with more detailed sources, but you'll get the overall picture. For more accurate (and again, sometimes slightly conflicting) information, try http://membrane.com/~elmer/rail/product.html , http://www.thedieselshop.us/INDEXMOD.html and http://www.trainweb.org/emdloco/modelsearch.htmoh sorry for the mistake, i didnt think there were diesels in use until like the late 40's.
well we learn something new everyday.