I'd say the doghouse on #476 was removed between July 1, 1953 and May 30, 1954.
Sorry, that's a pretty big window, but it's the best I can do at the moment. I haven't done as much work on #476 as some of the other K-28s .
With the exception of the AFE date, all of these are photo dates where the doghouse was either installed or not.
Installed before May 24, 1939: [
ngtrainpics.photoshelter.com]
AFE date is 12-31-1939: [
ngdiscussion.net]
Doghouse still installed on July 1, 1953: [
ngtrainpics.photoshelter.com]
Removed before May 30, 1954: [
digital.denverlibrary.org]
Still off on June 2, 1957: [
digital.denverlibrary.org]
Back on by May 30, 1958: [
digital.denverlibrary.org]
Still on June 22, 1961: [
morphotoarchive.org]
Removed again before May 3, 1966: [
ngtrainpics.photoshelter.com]