I'm settling on the oral version, "you rolling kings", since no other explanation really fits and I see no reason to go off to Zululand for an explanation. Old linking doesn't cut it -- it isn't typical of the way words shift around, IMHO, and linking was not a concept used for anything but anchor chain in the days of sail, also IMHO."You rolling kings" is a parallel construct to such lines as "my bully bully boys" or "me hearties", or "ye sailors brave and true" -- a fillip to the morale of sweating deckapes under rough conditions.
That's my story and I am sticking to it until other research appears to dissuade me.
Regards,
A