How to get the balls back in a ballnut?

[Clive S]

I have just come across this Linearmotionbearings C7 Ballnut Flipping and Repacking - YouTube as it shows in the vid how to re fill ball nuts etc. Clive

[John S]

That's assuming you have the same diameter at both ends of the screw.
If he'd just used a tube, no flanges and a couple of winds of tape round one end it then possible to use the same loading tube to switch to the same end. Just swap the 'safety' tape over.