adding Windows SBS premium to a Windows Server Basic domain

I am adding a Windows SBS premium server to an existing Windows Server Basic 2003 domain.

I have to demote the WSB server and make the SBS server the controller.

My questions is this… Can I just add the SBS server to the existing domain and have SBS automatically mirror the authentications and logons of all network devices, or do I have to go through each item one by one and add them to SBS?

Thanks for the help!