A number of years ago I spent about $50.00 buying a glycerin filled, 3,000 psi pressure gauge, and an inline needle valve. Along with that, a couple of short sections of hydraulic hose. Plus numerous fittings to reduce to, or enlarge to most fittings I have around here.
If you have a set-up like this, you can tap into your pressure line..., inline out of the pump with fittings. Make sure the needle valve is on the outlet side of the gauge, from the pump. Slowly close the valve, and watch for a pressure increase. You can close it clear off to see what the pump is making. But only do it for a very short time..!! As it may cause damage to the pump...
Not really sure what that pump will max out at though. Hmm., it may be in my service manual, but escapes me at the moment...
Sounds like you are having problems similar to mine. If I turn mine slow, I can turn it either direction with 1 finger. Even at an idle... Speed it up, and it's like fighting pressure from the other direction. Try and make a fast turn, and the steering gets real hard, either way. I assume my problem lies in the Hydramotor in mine. Another job, another day... It is just a spare, for cheap horsepower.
I did answer some of your questions in your other thread...
Good luck, and keep me updated on your progress..!!