The posts I've read about removing or replacing the automatic headlight on detector have always made this sound terrible difficult to do.
At least for a 2000 it is about as easy as tying your shoe (note a single shoe, not even both).
Like the dash surround, the vent panel in the middle of the dash under the windshield is just snapped in place.
Pop it out.
You will see the sensor attached to it. Like the instrument cluster lamp holders it is held to the now-removed panel by a ~1/4 turn socket. Twist it counter clockwise (normal fastener direction) to remove it from the panel.
In my case, I prefer to control when my headlights are on or off. Call me a caveman, I'm good with that.
I just put the sensor in the glove box. Pushed the wire back in and closed it all up.
Tested the headlight switch for manual function to ensure everything is copacetic. Now to remember I have to think when it gets all dark and scary.
I found an odd 'feature' of the panel dimmer: at the very lowest setting I could turn off all dash lights, including the odometer display. Might be due to a cheap switch, might be due to it being 20 years old, might even have been a design feature. Not bothered by it, just know that is my experience.