The 2 Migration Assistants (File and Repository) are independent of the SR that's installed. Whether you are using 9.0, SR1, or SR2, you should download the same Migrators – the ones posted under 9.0 SR1 on the New Version Downloads page in the Customer and Partner Zones. The File Migration Assistant was updated since it was first released, so make sure you have the latest version, which is the one posted.