Migrating Exchange Server 5.5 mailboxes

We want to migrate our mailboxes to a new server. We are using Exchange 5.5 and are running out of drive space and want to move asap. The sever we are moving to is a different server. Dell Powervault 715n running a stripped version of Dells advancedserver. Exchange is running on NT4.0 now. Do we have to install Exchange on the new server? We don`t want to if we don`t have to, we would like to have just the data files on the new server.