BN 4251 was built in June 1965 by Alco as the SP&S 311, part of an eight unit order of C425's built that year numbered 310-317.
With the help of the SP&S Historical Society and the SP&S Yahoo group I have a photo by Chuck Storz to share of the SP&S 311 before the BN merger taken at Vancouver, WA in September of 1969.
There were reports that the SP&S 311 was never renumbered before being destroyed in a roundhouse fire at Vancouver, WA 9-4-70 along with C424 4242 but again the SP&S Historical Society and the SP&S Yahoo group came through with another photo by Chuck Storz that there was indeed a BN 4251 as seen in this image at Portland, OR in July of 1970.
As a result of the Vancouver, WA fire the BN 4251 was scrapped.
My thanks goes to these two groups for supplying the images for this update and of course the photographer, Chuck Storz who took them.