Is this the "064" fan? It has the same # (914390)that preceeds the date code, and it looks identical, although dated B75...probaly just an over the counter replacement, or did GM use the same fan for different applications after 1970?
http://imagehost.vendio.com/a/358018...w/IMG_4200.jpg
http://imagehost.vendio.com/a/358018...w/IMG_4201.jpg
http://imagehost.vendio.com/a/358018...w/IMG_4202.jpg