I was able to catch Railserve GP15 697, and SSRX GP38 3670 climbing up through the canyon between Garfield and the Kennecott Smelter. They sound and looked good in the evening light.
Even though it been here awhile. I finally was able to get a picture of Railserves GP15, in use at Kennecott Copper. I've only ever seen it up to this point hidden up in the smelter.