Caboose
Caboose 1074 taken on the Matanuska Branch on a gravel train in the early 90's. You can see why the confusion has arrived as to blue verses black. If you are careful in examining this photo you can see the Alaska and the band on the side are definitely black. The cupola is also black although the dirt, weathering and atmospheric conditions and optical shift from being adjacent to the yellow side gives it a blue cast.

 
Photo courtesy of Pat Durand