Ignore the door decal if it doesn't match, easily swapped out. Check the underhood build plate too, and how attached. Also, the rivets holding the dash plaque.
Oh wait, no cowl tag? Run. Not good.
Oh, saw VIN dash plate too. Not good either, nothing else on car matches '79 where it differs to 80/81. And that dash hole looks hacked up, sanded and filled. Not at all how it was from new. Bad news all round.