Well this is interesting.

There used to be a pretty extensive write up about making a hydraulic control for these- on line since the 90's.

That's about all I remember except that maybe the author's name was Pat.

Yea, I have read craploads on it, but they didn't really tell me anything I didn't already know.
Maybe a few little details but I didn't like how a lot of people did it anyway.
I'm kinda like that.:D