duxthe... It's not that I don't believe you, I'm just not fully convinced! It did the same thing with the OLD and NEW water pumps installed.

Adding water ( if you add enough ) would make an instant change as soon as it hits the belt. If it doesn't, the problem isn't the belt / flat pulley.

Another thought, is the fan rubbing the shroud?

I've had good alternators make a whining / whistle magnetic noise that increases with electrical load.

Given you have changed a bunch of stuff and the noise stops when the belt is off, the likely hood of something flying off is low so I'd say drive it and check once in a while. Also please post a final result if you find out what happened.

The fan is clear of the shroud. Even with my stethoscope I still cant pin it down which is what irritates me the most. I really didn't mind replacing the "front of the engine" parts; at least I know they are good, and I believe I saved myself from water pump destruction. DUXTHE may be right, it may be the new water pump seal, but its just too coincidental that it did it before I changed over the pump and I don't like coincidence.