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May be the AC compressor idler bearing. Replacing AC clutch without disconnecting the lines will be your most affordable option. Posting your engine helps. I followed the video and replaced mine with a junkyard unit many many years ago. Levered it off with a few large screwdrivers. Still working great to this day.

 

Yeah that's one I watched yesterday. Good stuff.
Is the idler bearing the one on the pulley? The noise doesn't happen unless the compressor is engaged.

 

If you don't get the noise when the compressor isn't running, then the idler bearing is fine. Need to verify what is squeaking, if it is actually the compressor itself, its replacement time.

 

I'm going to start with a new belt and do a visual on everything that connects to it. There's a cold snap coming so I may not get back to it until things warm up a bit. Then I'll check the A/C temp at the vents to make sure it's cooling. I'll try to record the sound it makes if I don't find anything obvious.
More to come. Thanks for the help.

 

Take off the belt and spin everything in it's path that you can by hand. All the pullies water pump, etc. Nothing should be dry or chalky. Grab the fan blade and rock to an away, there should be no play.