Many will suggest Alamosa, but I would suggest Salida. Salida was on the main line, whereas Alamosa was almost at the end of a branch line. More of the D&RGW larger power operated through Salida, giving a good comparision. One of my favorite shots was on the cover of Trains Magazine in 1940. It showed a D&RGW L131 2-8-8-2 coming throught the yards while two D&RGW K37 2-8-2s waited to cross the dual gauge main line.
A famous Beam photo shows a D&RGW K28 (472) next to a 4-8-4 at Salida. It shows the size difference very well. I think you can see this one on the Denver Library web site.