John:
I do not want to repeat the article, but 278 was in snow plow service on Marshall Pass in the mid-20s. Prior to that it was used on the Lake City branch for a long time. 278 worked in Salida as yard switcher with dual gauge couplers from around 1927 until 32 at least. When you read the article, you will see 278 at Salida in 32. In 35, it was in Gunnison and in use on the Baldwin branch with 223.
All of the D&RGW and RGS rotaries except OO got ex-C16 tenders. I have documentation showing the D&RG charing the RGS for a tender for RGS Rotary #1. There was discussion here about ON and someone said that Gordon Chappell found ONs tender with lettering for 243 showing. The D&RG beefed up the C16 tender frame with what looks like an extra frame. They also added enclosures over the coal bunkers. OM and OY had peaked enclosures, while RGS 2 and ON had square shaped enclosures.