Dan- I'd say that unless you copied info from the builders plate, it's new number may be lost to history. All I can say is it's ex-GN. Boxcab E50
Dan, I'd say between i would have been numbered between 1761 and 1792. As a matter of interest, have a look at trhis... http://archive.trainpix.com/BN/EMDORIG/GP9/1791.HTM Familiar? Check the BN archives for left hand views to narrow down the possibilities for two-pane all-weather windows - some had three-pane. Hope this helps.