[Jared]

I think Frizzen was suggesting instead of using a pump driven system, you could use a servo pushing on a separate cylinder to drive the steering cylinder/s, sort of a master and slave setup. They would have to be equal displacement, or close to it. It would in effect be a remote mounted steering servo. Bleeding the air might be an issue, though.

Using two steering cylinders is certainly possible, though. I built a hydrostatic steering system on a 1:1 Farmall tractor with two cylinders that I'm very happy with.