I wouldn't rule out snowplows on 474 or the 490's not listed. Allow me to digress. For much of the 1930's and 1940's, the K-37's worked out of Salida on Marshall Pass and on the Monarch Branch. Given the amount of snow there (as well as on the Crested Butte Branch), use of pilot plows certainly could be warranted. Those lines never did garner the photographic interest during that period, compared to the photographic frenzy that occurred at the end of the narrow-gauge era in the late 1940's, 50's and 60's. That may account for the scarcity of "plow" photographs of the K-37's. It was also more typical in earlier years to remove the plows during summer and replace them in the fall.
When the San Juan Basin drilling boom began by the early 50's, all of the K-37's were moved from Salida to Alamosa (prior to removal of the "Valley Line" from Salida to Alamosa), presumably because of their heavier tractive effort. They also were more "temperamental" and probably needed to be near the large Alamosa backshop.
K-36's 480, 481, 482, 483, 485, 486, 487, and 489 were moved to Salida to protect service there. Around the end of 1951 or early 1952, 487 was moved via the standard gauge to Alamosa. 485 fell into the turntable pit in Salida in 1954 and was scrapped. Thre rest of the 480's in Salida were moved via standard gauge to Alamosa when operations over Marshall Pass and then narrow gauge operations at Monarch wound down. 489 was the last engine overhauled in Salida before the shops there closed.
As for the 474, it was unique. So far as I know from research, it spent nearly all of its career working out of Salida. I was told by a reliable source that, unlike the other K-28's, it was never equipped with a steam heat line to supply steam for heating a passenger train. Thus, it could only be used for passenger service in the summer. Nearly all photographs I've seen of it show it in freight service. 474 was used quite a bit on the Crested Butte Branch and very likely would have sported a plow during winter in that service.
Trivia, trivia. But fun to research!