I had the idea a long time ago to use a power steering pump from an older import car (domestic cars turn the wrong direction). An older import would have a V pulley and many used a remote reservoir. I figured it could be mounted the same as a NF factory pump, but plumbed to use the transaxle as the reservoir. I never got to try it though. I was told the pumps should have enough suction to pull fluid from the transaxle.
BTW, if using double acting cylinders the level won't change much once the system is full.
BTW, if using double acting cylinders the level won't change much once the system is full.