I decided to watch this movie the other night. I actually did not know how many different train scenes this movie had.
The movie was copyrighted in 1971, after abandonment.
I'm not sure I got the railroads completely right, but I think these are all of them
Durango and Silverton (478 pulling a short train)
The second train I think was the Union Pacific 119 replica (was it even built in 1971?)
There was also a shot of 483 painted red, black and gold, and with 577 painted on the numberboard.
Did I miss anything?