Reynold checks out the GP 39 locomotives of the SS&P, which is a subsidiary of Omaha Track, as the lettering on the middle locomotive reads. SS&P operates trackage owned by the state (as does the Wahington Eastern) south to Palouse, Washington. Traffic is mostly grain, but also lumber and other misc. loadings. According to Google and another source, the BNSF also runs unit grain trains on SS&P tracks from Marshall to McCoy, where there’s a large grain loading facility with a balloon track.

Here's quote from Google: "The GP39-2 "High Cab" Fleet was ordered by Kennecott Copper between 1976 and 1980 and consisted of 32 upgraded GP39-2 locomotives. The vast majority of these were famously custom-built with "Vista Cabs" (raised cab roofs with extra windows) and high-clearance fuel tanks. This design was requested directly by Kennecott to maximize engineer visibility."

Another item from Google says they were all ordered new from EMD, as opposed to the "upgraded" remark in the first statement. (?)