Try checking with your local lawman, if you have any friends in the buss. it helps. it might not be in the file, here in calif. they purge about every 20 years but it's a starting point. If you get the VIN it might help. also if you have any private vehicle reg. business I've had good look tracking down owners that way.
Good luck it's a great car, a kid in high school had one with small block, shellby sorta, ran like heck.