These days, there would be a generator car in the consist someplace. No HEP back then, with steam heat. In LA, there might be no need for heat at the time, and iirc some passenger cars had their own generators for lights & a/c. So using freight motors for local runs might have been feasible.

As for track arrangement, thanks, but I needed a little more info. OpenRailwayMap helped me envision it: [www.openrailwaymap.org]