GM/ Delco power steering pump and compressor?

[Guest jbenini]

Greetings all, I have a mystery power steering pump/compressor on my hands. The power steering pump looks very much like the one on my '57 Buick, but it also has a V-twin compressor bolted to the front of it. I looked through my Hollander interchange book thinking it was for an "Air Poise" '58 Buick or Cadillac, but the number doesn't match. The manufacturers build plate on the bottom reads "Delco Products, a Division of General Motors, Dayton OH USA" and "Model # 5540180" I've attached some photos, I'd like to identify this and get it into the hands of someone who can use it! Thanks for your help, JB