I went up and looked at a few RGS dispatchers train Sheets. It would appear tha the RGS ran their EB lite helpers trailing the train, Mancos to Dolores, Lizard Head to Placerville and ran them ahead Peak to Ridgway. At least in Sept of 1937.
According to the Dolores Train Registers for 1926, when they were running both scheduled freights three days a week and extra freights the other 3 days. Mostly three engines, The train would preceed the helper into town both from the east and from the west. On the scheduled train the helper is listed as the second section, the
First section carrying green signals. On the Extras the helper is listed as an extra. In both cases the trains arrived with two engines, and the single helper following.
Hope this is clearer than mud
Dave G