Re: D&RGW 470s: differences over time and between units

First thing is that steam engines are usually not called "units", but something like engines, steamers, steam locomotives, etc. Units are generally associated with diesels or electrics. Sorry had to bring that up.
The ornament on the 479 was seen while on the Shavano Passenger train, which ended in 1940. In our video Rio Grande's 3rd Division, there is a black and white shot of it backing into Gunnison, and it is clearly seen in that shot.
Cannot answer your questions regarding the engines that went to Alaska in 1941. The 473 was the Durango switcher for several years in the 50's and 60's. It was the last of the remaining 3 K-28's to get the diamond stack. In the video "Rio Grande. Vintage Steam" there are several scenes between 1955 and 1963 of the three K-28's, especially 473. 476 also was modified several times for movies, with fake stacks, big headlights, new numbers, and tender lettering changed. I don't remember all the details, but we got a lot of the info from Earl.
Greg