replaced bad water pump, now I get a high pitched noise above 4k rpm. any Ideas? does it need to "break in"? belt tension seems good, not too loose, not too tight. doesn't sound like a belt anyway. I guess I should remove the belts one at a time and see when/if it makes a difference?

 

Do you have a double pulley for the alternator or the factory system in place?

 

Probably belt noise.

 

stock alt pulley (new alternator) new belts, doesn't sound like a belt to me, sounds like a bearing/.metal noise

 

Hard to test without removing belts or swapping components. You could try an automotive stethoscope or super long screwdriver and listen for the noise at each component.

 

New belts can squeal at high rpm. I recently had to tighten a fresh belt when the rpm went over 5000.

I had a bad, old water pump make a whining noise at idle, does it sound anything like mine did?
Last 5 seconds of this video:

 

update: the belt was TOO tight, I hope I didn't fry the bearing, but it seems ok

 

The alternator and water pump bearing shohld be ok given the fact that you weren't driving in it for thousands of miles. Glad you were able to get it sorted out!