Automatically assign "Position" when ordered by name

Hi there... possibly along the same lines as what this guy was after but I'm not sure:

https://support.emagicone.com/964151-Sort-Re-ordering-Attributes-options-positions

Anyway....

So I have a list of options in an attribute for "colour"

There are 100's of options
I need to sort them
At the moment I have to manually SORT by the colour name and then assign the position manually

It would be great.. to sort by options... by name
So all colours are in A-Z order
Then press a button which will automatically enter.. the positions needed to maintain that sort order.

So you sort it A-Z

then it will set the positions.. to 1,2,3,4 etc etc