Assembly is reverse order. Lubricate the hose OD and ID with power steering oil to make it easier.
Start screwing the new hose into the shell a few turns. It is a left-hand thread so turn ccw. As soon as you have room, push the tube mandrel into the hose ID and turn in 1 turn cw to get it started. Don't wait until the shell is all the way on or you may not be able to get the mandrel into the hose.
Continue screwing the shell onto the hose (ccw) until the end of the hose bottoms out in the shell, then unscrew 1/2 turn (cw). Then, continue screwing the mandrel into the hose ID until the mandrel bottoms out against the shell. Re-install hose on pump and gear, routing so it doesn't touch the car's body.