My bird was re-VIN'd in WI before I got it(WI replaced the door jamb tag) and they added some zeros and changed the "U" into a "4". I suspected it was supposed to be a "U" but I always wondered how bastardized my bird really was. Seeing the numbers on the cowl match my re-VIN,save the U/4,makes me feel a little better. I think I remember something about numbers on the rear but mine is so pitted if they were there they are gone now.
On a side note when I registered it in Oregon I tried to get them to correct the U/4 but they wouldn't...perhaps now I can try again.