Metallic squealing noise from engine > 2k RPM

2005 4.0L V6

There is a metallic chirping / squealing noise coming from the engine area over 2000RPM, so every time I shift or I'm on the highway, it's constant.

This started a while ago, and I have changed, in this order:

-Alternator
-Belt
-Belt tensioner
-Fan clutch
-Idler pulley

Still no change. I'm at a loss. It seems like it could be anything turned by the belt or even the aftermarket parts I've already replaced, which is frustrating.

It's pretty annoying / embarrassing to drive at the moment. Any ideas?

I feel like the water pump might be the next thing to check.