1990 740 Turbo, frankensteined from other cars, thank you kruse-lucas.

The power steering pump in my car has always sat loose on the mount for it. It seems like the mount on frame cross-bar/engine support for the power steering pump is worn. The triangular sheet metal parts are fine, but the pump has always wobbled some.
It's gotten worse- so much so that the pump started squealing and the steering stopped working beyond about 1/3 turn of the steering wheel. I flushed the fluid in the past by removing the return line. The reservoir level never fell below the return port.
Tonight, I fitted two washers between the mount on the engine support and the pump's sheet metal mounts. This secured the pump well after I tightened everything up. I thought it would be awesome, my squealing would be gone. I found out the squealing is gone, but the steering still works like crap. I drove to my girlfriend's and found the fluid in the reservoir had a "head" of about 1mm of bubbles.
So, I'm thinking my pump is going bad and quickly.
Before anything else, I'll be flushing the fluid again and probably installing a magnefine filter. If there's a good alternative, I'd appreciate some info.
One thing I think important: I used plain jane power steering fluid when I flushed the fluid, not ATF. This could be relevant, I suppose.

As far as replacements, the Crown is 120 (less 35 core) and Scan Tech is 229 from FCP Groton. Any feedback on the differences? Does the Crown suck?


Thanks,
Will
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1990 740 Turbo, on its way to stock specs, maybe beyond