NW SD39 green livery

[nw-modeling-list at nwhs.org]

Hello,

in the web i found two pictures from green painted N&W SD39 (former Illinois
Terminal).

Pictures see:
http://www.railpictures.net/viewphoto.php?id=102650
and
http://www.railpictures.net/viewphoto.php?id=50384

Does anybody know how many of these green locos have been used byN&W?
How long did they wear the green livery?

Thanks
Claus-Juergen Prenzel (germany)