want to migrate some sites through my multisite

heya. So … I have decided to make a secondary site within my multisite the primary.

specifically, i want http://www.mythica.intothemythica.com to replace the primary http://www.intothemythica.com.

I would like to move the * current * prime site to a secondary site and replace it with the * current * secondary. I’ve had some timeout issues trying to clone it as a site though. Assist?

Any things I should be concerned about? What’s the process of doing this?