Got to looking at my stuff on this again. Answered one of my own questions as to how the connections were made at Durango for the Farmington Branch...See attached timetable info:
The wire numbers were (left to right)
1 3 01 5 S1 so102 2 108 109
At the time this particular timetable info was in effect, circa 1926, it says there were repeaters at Durango for the two Farmington Branch wires, DS wire No. 1 and RR wire No. 2.
The question remains "where were the repeaters located?" I would surmise they were in the Durango W.U. office, since at that time, The W.U. still maintained the lines and equipment for the Railroad.