DGLE (dark green locomotive enamel). It's virtually black with a hint of green. Many model train manufactures seem to produce it one way and then others in term of pigmentation even on the same locomotive type release to release. But closer to black than green is regarded as closer to correct.
In 1943 the PRR bought six surplus class Y-3 2-8-8-2s from the Norfolk & Western, including No. 374 (the former N&W 2008), designating them as class HH-1. The first L/AF release had a whistle more reminiscent of the hollow or haunting N&W type. (That was partly the reason I bought two.) Second release is definitely higher pitch. Not sure if it's what a PRR HH-1 sounded like.
Photo: Don't know if PRR ditched the doghouse. Might it be the doghouse peeking over the back rim of the coal bunker's edge? http://rrpicturearchives.net/l...cture.aspx?id=235593
PRR #374 was previously a 4-4-2 Atlantic: http://rrpicturearchives.net/l...cture.aspx?id=241926
In any case, enjoy yours. That's what it's all about.