I was informed "I've never seen something like this. Looks like your trucks determined to be squeaky"
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No, that's someone who just has given up.
There's a reason for these things. You just have to be systematic to find it.
90% of the time is is tensioner/ider or belt related. When it's not one of those the "experts" just start throwing parts at it.
I wouldn't change the water pump yet. Take the pulley off it and make sure it is seated properly and the mounting surfaces on both the pump and pulley are clean. Reinstall it without the clutch fan with shorter bolts if needed. While the belt is off, turn the WP by hand. Make sure it turns evenly and without "hitching/ratchets". Then install the belt, run it and see if the noise improves/changes.
Did you change the tensioner assembly or just the tensioner pulley?
The tensioner spring in the arm sometimes goes weak over the life of the vehicle and doesn't tension the belt properly. It will still be in the middle of the adjustment range, but it can slip due to not enough tension.