Well, that's the SN car with some upgrades! Really nice job though and much along the lines I was thinking. I am also quite taken with the SN No.1 Stover railcar that Mears/Pitcher had back in 1908 and the only picture I have seen is the one in the Rainbow Route. I would think a larger vehicle like the Stover built on a modern truck frame with current gas or diesel engine and power train could form the basis of a reliable piece of equipment.
The vehicle in my original posting is indeed from the Western Colorado Power Co. Under the coat hanging over the seat can be read "Weste...Power." The round sign hanging on the corner of the depot has Western Union in the center pointing arrow and "Telegrams and Cable" on the round, outside edge. But rather than being transportaion to Tacoma, I believe this car was used to maintain the line from Tacoma to Silverton. The original power line as built was along the Animas all the way into the substation here. In the late 1930s it was moved to the present location over Coal Bank and Molas Passes. Power crews working at Tacoma have always come in from Rockwood. The Tacoma plant was built to serve Silverton and initially had no connection to Durango.