Is this rare? I ran into the owner, and it turns out he was the original owner. He said he bought the car brand new in late '89, and it came factory with the sunroof. I have never seen one before, so I am assuming it is either rare, or he is pulling my leg on it being factory, but it sure looks factory.

Its possible. The bonnevilles got them in 90. Many dealers also put in aftermarkets. You can best tell by the switch.

Its factory. It is rare also as I've only seen it on a handful of cars in junkyards. I know of an '89 Bonneville with a factory sunroof and a couple T Types have them as well.

i see more with sunroofs than without on bonneville SSE'* from 88-91. but i've only seen a handful of lesabres and park avenues from that era with sunroofs.. We had a 86 Park Avenue Electra and it had a factory sunroof. but it was very very loaded with leather, and even BOSE sound system.