No power steering fluid is used. Alternative for the power steering is ATF.
"Quicksilver Power Trim and Steering Fluid or automatic transmission
fluid (ATF), Dexron, Dexron II or Dexron III."
Is the Mercruiser hydraulic fluid red like ATF? The stuff in my power steering was red, and I just topped it off with ATF.
For drive trim, "If quicksilver Power Trim and steering fluid is not available, SAE 10W-30
or 10W-40 engine oil can be used in the system."