Migrating VPS info into a shared server "client"

[masconcable]

Hi

I need to migrate all domains, settings, dbs, emails etc hosted from a customers existing VPS server into a "shared" server ..with multiple existing client accounts.

Both systems are Linux with Plesk, destination uses Plesk v8.6 ..unsure of current server version but older than 8.6

Can this be done using the migration manager without affecting the existing client accounts or should I ...

1. create a new client account on the new server
2. run Plesk backup on the existing server
3. import backup to new server and restore

thanks