ok, this is a real puzzler for me...the serial number on my Centurion is N9H6093. From what I have read in this thread and over at Sheldon Brown's site...I gather the bike was either a 79 or an 89. In either case it makes me wonder why my wife told me it was her bike when she was in college between 1973 and 1976...I do remember that the frame had a tange sticker on it prior to the sandblasting.
