Yup, that was me. I'll start a separate thread on the spool valve rebuild. The motor oil or the tranny fluid will work, but the hydraulics expert from the maintenance dept where I used to work said that I would be better off with real hydraulic fluid. He said modern fluids were better for o-ring & seal life, and would foam less & outlast the others. The only disadvantage with hydraulic fluid is that is usually lower viscosity, and may leak more, especially in older, already leaky units. He said that was good, tends to wash the dirt away.
(I think he was kidding)