How do I know what trim package my Towncar has?

It's a 1989 Lincoln Towncar with a 5.0 302 V8 engine, automatic 4 speed with overdrive, leather seats, power everything, no moon-roof, a full vinyl roof, automatic climate control, woodgrain, no digital dash.. I don't know how to find out the difference between base, signature, signature se, and cartier. Thanks.