[William]

Start by going through all the paperwork that came with the car. Was there a vinyl pouch in the glove box? That's where the owner's manual and original warranty folder would have been stored.

There's a tag in the engine bay on the firewall behind the power brake booster. Post the information on the tag. Someone here will be happy to de-code it for you.

You may be able to research ownership history on it. Every state is different; some retain history many years back. Some do not.

Congrats on the acquisition!