Benkku

HI! I found a GT-80 that has all the lights & turn signals, so I'm going to register it on the street just for the little runs around the neighborhood. I got no paperwork with it from the seller, so how do I go about determining what year and model it is? Obviously, I know the VIN. Does it tell any of this info? My bike has grey tank with red stripes, a bit like 1974 MX360. My 1974 MX 250 has same grey, but then yellow stripes, same style. I also have another GT80, but it's been painted over, I guess. Same problem. no paperwork and no clue what year & model. Furthermore, I'm a bit lost in what to model abreviation to use with my, what I believe is 1966 Ascot Scrambler. Has good numbers, right stuff for an Ascot, but what is the model? If someone has info, please let me hear from you, thanks!