Bang bang (on / off) solenoids on hydraulics are fine and you can use the lever in my case on the steering column to vary the flow, however beware when tipping as flicking the switch with the lever locked in full flow sends the tipper up like a catapult!
You'd be surprised what has proportional electro hydraulics on - hedgecutters, diggers etc so have a look on ebay and I could have a spare soon as well.
Will take the pics of the output pto and wedge in another forum when I get to them.