We are just trying to help.
I don't know why the legitimacy came into play.
Probably because you said it was from the original owner that "knows nothing" about cars but yet the car has a non 81 nose, mirrors and probably tail lights that look like they all match the paint perfectly.
And that the cowl tag is missing which that in itself could be a felony if it contains any of the VIN info on it. It is here in NY.
Like I said I don't know.
Just trying to help and not questioning what you know or what you were told about the car.
I will tell you this.
The state will allow you to register it, plates and all
About a year down the road it may or may not throw up a red flag.
If it does throw a red flag then it gets forwarded to the State Police
A year or so after that when you go to re register it they wont let you tell you you have to bring it to a State Police Inspection Station or the State Police will be at your house with a tow truck and shinny bracelets.
Did 81's come with that header panel and mirrors?