GameCentre shared leaderboards

Hi all,
I have a paid version of my game that is currently on the App Store, but I’m working on a free ad supported version. How easy is it for me to share the leaderboard from the paid version with the free app?
I know I can set up a leaderboard group but can I transfer the existing table in without a) wiping it, and b) having to update my paid app?

Cheers
Chris
[import]uid: 7841 topic_id: 34419 reply_id: 334419[/import]