This is a common mirror - Donnelly 012017 - electrochromic, very nice, used on a variety of cars. For google search results, this is likely found on Buick Regal and Century models from 1997 ('97) to 2004 ('04). Possibly on others - Park Avenue, maybe some Chrysler models, who knows.

So there are two types of mirror mounts - the ones that clip on, and the ones that have a screw. Dismounting the kind with a screw is trivial. Dismounting the kind with a clip is annoying, mostly because of the incredibly vague instructions: "The rearview mirror is removed from the support by prying with a small flat-bladed tool." The shop manual is similarly vague: use a small flat-bladed tool to remove the mirror. Awesome. Useful! No, just kidding, not useful.

So here's what you're looking at. There's an oval-shaped mount attached to the mirror; the mount is clipped onto the rearview mirror support. The support is nice and metal, which is important because of how we need to remove it. At the bottom of the mount, next to the glass, there's a nice opening. Grab yourself a sturdy flat-bladed screwdriver - preferably 4mm, so on the large side of precision screwdriver. Stick it in the opening, all the way until it doesn't go farther, and pry down, and up. You should see the entire mirror move a bit. You're prying against metal, not your windshield. Keep prying until the entire mount pops off. You don't need to pull the mirror, just pry until it pops. It feels a bit like things are going to break, but it's the only way to do it. Once it pops, you're done! There're some more details after the jump, if you care.

Do yourself a favor and try to replace it with the screw mount. That kind slides on and off nicely, and then you use a hex or torx screwdriver to firmly secure it. Replacement cost is $40-70 on ebay, depending on shipping and tax, or probably $20 from a junkyard. Make sure the model number is right and it takes the 7-pin connector.

Looking at the connector from the perspective of the mirror, right to left (right is pin 1), you have:

• Brown - fused ignition 3 feed
• Black - ground
• Light green - backup lamp feed
• Gray - automatic day/night mirror signal - outside
• Pink - automatic day/night mirror return - outside
• Gray - interior lamp output
• Orange - courtesy lamps battery feed

I don't know entirely what those things mean, and I believe the mirror uses only four of those wires.