Great shot Dick!
This was probably 1982 as we didn't start the summer Cascade service (Trains 265/266) and the new San Juan service (Trains 115/116) until June 1982.
These trains shared the same train set with 116 arriving at Durango at 3 PM, It was then serviced and cleaned, with another engine put on (or the same one serviced) and turned around as Cascade 265, departing Durango at 4:30 PM with a fresh crew. It would arrive back at Durango as 266 at 8:15 PM.
This was loads of fun. I was the regular fireman on 115/116 in 1982, Sometimes the railroad would be short of crews for the evening Cascade. You guessed it, the entire 115/116 crew would turn and take out the Cascade for the evening. Those were loooong days with a usual 6 AM call for the San Juan and tying up at 9 PM after returning with the Cascade. The Cascade did all the switching at night as well! Some of the assigned Cascade crew (engineer/conductor) didn't like it as they would be short a some hours after working a 5 day week, unless there was lots of switching to do. The help, management would swap out the engineer every other week with the engineer and conductor from the San Juan. This seems to even things out a bit.
Below, D&S Employee Timetable No. 1, March 25, 1981 and supplemental schedule as revised for June 17, 1982. Timetable No. 2 was not published until 1984. I would fold and tape the schedule inside the Timetable. This one is right out of my grip!