How do i make a specific group primary

I have enabled the option to make my default group 'hiddenifnotprimary', and have assigned myself to my 'Owner' group. I still have the default group tag, though. 

How can i make my 'Owner' group primary when I add myself to it, therefore cancelling out the 'default' tag?

Thank you in advance to any of you who can help!

The primary group is determined by the groups priorities. Out of all the groups the player is a part of, the one with the highest priority (the lowest number) is their primary group.

Spot on, mate. Thank you for the help. I had the priorities the wrong way round. 

Dazz

Merged post

Is there a way to add an entire usergroup to a chat group? rather than player by player? I'm quite shit at this, to say the least.