I made a video, hope it works
​works. https://youtu.be/D1vC3jgyyhwI replaced the transmission filter and fluid, and tensioner and pully and belt, and I put a new alternator in. Whine is still there, maybe worse than ever.

I also went lock to lock, engine on and no problems, no noise. I don't think it's the power steering. Maybe idler or crank pulley? I'm running out of things to replace.

 

Its power steering. Check fluid level. If ok replace pump and flush. Fill with correct GM power steering fluid

 

PS fluid level is ok but more brown than pink, for sure. maybe a flush will work... Or an additive?
The whining seems to be located in the idler pulley area. The pulley looks like tts running smoothly but without the belt it has some drag. With a finger-spin it won't turn 360.
I grabbed the PS pulley and it does have a slight in-and-out movement. Not enough to measure, but enough to feel. I also checked the other pulleys and they are firm.

 

To me it sounds like it's ready for a new p/s pump. But I've been wrong before! Use your best judgement.

 

Thanks, Led. I was able to pinpoint the noise with a screwdriver on the bolt in the idler pulley. Installed a new AutoZone pulley and the noise is gone.
I guess the upside is all the work. I did tracking down the noise. I put a new transmission filter and fluid in. I put a new alternator in. I replaced the air filter and clean the throttle body. I installed a new tensioner and belt and after looking at my power steering fluid I think I'll change that out too.
And while I was under there I lined up the wheels so my steering wheel was not pointed at 11:00.
All that should give me some maintenance relief for the next month or two!

 

Glad to hear you have a successful repair!