Sooner or later you may have to reassemble a Ball Nut. This is not a difficult process, if you look on Utube there are several examples.

 

However, if you only need to swap over a ball nut, so the flange is on the other side this can be accomplished without removing the balls 

 

First make a plastic top hat of the correct diameter. If your screw has a machined end, you can drill out the centre of the top hat to push over the Screw end to aid location.

 

The balls will then ride up off the screw and stay in place on the top hat. This can save hours.

 

However, reloading a ball nut from scratch can be done quickly, after a little practice i managed to get a Thomson Sigor, ball nut reloaded in 15 mins.

 

The photograph on the left shows the plastic guide I made to reverse the ball nuts. Note the hole in one end which fits over the screw end to aid starting the nut and engaging the balls.