so again while im waiting -- im a new gg owner, got a stealth and a TS in the latest batch from esmokeguru which arrived today

and i have an ithaka preordered from CoV as well -- problem is my better half is only going to let me keep one as i've overspent terribly this month on
vape gear -- what parts do i need to be able to "build" both a stealth and a ggts? i mean to say, if i have to part with my stealth, what do i need to
buy to convert ggts into stealth -- just a stealth cap? or a stealth cap and rethreader? or more?