[Kevin Sevcik]

As others have mentioned, a better option it two single acting solenoids, one plumbed for 60 psi, one plumbed for 10 psi. That or a spring return cylinder would work best. The obvious downside to the spring return being that the spring return force is going to decrease your extend force.

The problem with your proposed solution is that regulators are mostly one-way devices and don't allow unrestricted flow backwards. So you'll end up with the retract side of your piston still partially pressurized when you extend it again. Which might not be a problem for you, but wouldn't be as optimal as having two single solenoids.

Al:
I've always read that as meaning you can only have one regulator that knocks your 120 storage down to the "safe" 60 pressure, but you could have further regulators after this main regulator if you had a reason. Basically, that you were only allowed one connection from your storage battery to the entirety of your valves/cylinders/etc. Q&Aing it can't hurt, but I'd assume a secondary downstream regulator is legal until the answer came back.