Power Steering Noise

Have been chasing this for a long time and it is driving me CRAZY! 360 engine in 69 Cuda with Saginaw pump. Idles fine and steers lock to lock with no noise. Somewhere above about 2500 rpm it starts squealing. Can’t really decide if it sounds like a belt squeal, or more of a screeching.

PS belt runs the water pump and PS. When I take this belt off, the noise stops.

I have changed the whole front end of the engine from 69 Frankenstein belt setup to 70 up. Changed water pump, fan clutch, water pump pulley and power steering brackets. Both PS hoses new. Still did it. Just changed out power steering pump. Still does it.

Fluid level is good. What else could it be? Kind of sounds like it could be air getting in ps system, but where from? Could it be the steering gear? I am about to start drinking more than I do already....