How do i figure out what year my porsche 912 is?
 

I recently found a porsche in somewhat decent shape in a barn, so I bought it for super cheap. Its a 912 and there doesn't seem to be a VIN, or at least not one like I'm used to seeing these days. The only numbers I could find on it are on a tiny plaque in the door jam x431 v pro. The numbers are 455664 and 6608. The guy says he thinks its a 1966 and the numbers both have 66 in them, so I'm assuming he's right. Can anyone confirm that for me?