I have a similar problem. mine is an Eldorado, so the door is longer and there is no frame around the glass--so it's inherently noisy.
Here's the best advise... go to a Cadillac bodyshop. They're about $60 an hour and it should take half hour to fix. I almost did it but the folks I went to are closed on the weekend. I went in person and that's what they told me to do.. come back when the guys are in.. blah blah.
It is a real touch and feel thing on those door adjustments. The Eldorado gets far more complex and can involve adjustments inside of the door. The Seville is primarily related to the latch and striker.