I just installed a different PS gearbox and the steering is not quite right. The steering wheel is "jumpy" and it want to keep moving in the direction I turned it. I went lock to lock a number of time to get the air out. what else could it be? It was a used gearbox so I know nothing about it. The pump was working fine before I took the other gearbox off.

I think your problem is still air in the system. Go out and drive it a short distance, return and steer it lock to lock, then let it sit overnight. I think it will be fine tomorrow.

It's also possible you're using a gearbox that requires higher pump pressure than your pump is capable of putting out, or that there is debris in the lines somewhere.

The gearbox is supposedly off another 71 but it was a salvage part so I know nothing about it. The oil is terrible...I keep draining what I can and replacing it and as soon as it circulates, it is bad again.