Exchange 2K – “combining” AD

We are moving our HQ E2K server (& its the only AD machine there- all others are NT domain machines) to a new server machine in a new location. We have a new AD in the new location. Old E2K server is staying put as a remote with all mailboxes movingto new location. What is the smoothest way to do this? My thinking is to install E2k on new server, join existing AD and bring the inf stores down to new server, dcpromo the old E2K box to kill AD, then rejoin old E2K box to new AD.
Any help wouldbe appreciated!