Yep, I looked for prototype photos to post but gave up after an hour or so of searching for one that shows the door/pump conflict like the one that you attached.
As for the model, that lower portion of the 'firebox' should be the ash pan and not have staybolts below the frame line. I'll have to speak to the modeler.
As to the "Gunnison", this
is a "kitbashed" rendering of Eureka & Palisades No. 4 Eureka as originally modeled by Jon Davis. Colors were taken from David Fletcher's 38 Class artwork found in
Denver & Rio Grande, The Early Years, Page 77. Scrollwork inherited from the Eureka.
OBTW, the ash pan on the 56 Class, which extends down past the frame, is clearly displayed in the plan on Page 80 of the above work.