I removed the belt and spun the idlers and all the accessories and everything seems smooth. With the belt back on I ran this thing for three hours at varying speeds with ac on and off, and with a load on the engine. No luck, no noise.
A week later the car owner comes in while the noise is happening. Woohoo! Finally I got to hear it. As soon at the headlights are turned on the noise starts and it sounds like a failed bearing in the generator. When you shut the engine off and restart it, no noise, until you turn on the lights.
Picked up a generator and changed it out today. My arms are tired. The AC compressor has to be removed and the generator then comes out the bottom of the engine compartment. Without a lift here it was all laying on my back reaching up. I'm going to sleep good tonight.