>> By "post to the group after" - how does that work??
It means that you will have to figure out your own way to cut each message out of the YG (or your incoming email client) and cross-post them into the new group, in some manner that you find the least objectionable.
I know of no way to force the messages to appear to come from the original poster. If you have a lot of time on your hands, you could insert some text at the top of each such message stating who originally posted it, but the message headers will still show you as the cross-poster.
Bruce
Bruce