ESS/MSS (SAP ERP 2004) and ECC 6 backend system

We have EP6 linked BP ESS/MSS (SAP ERP 2004) and ECC 5 backend system.

We want to upgrade ECC5.0 to ECC 6.0 and use the same BP and EP6.

According to Note 965365, 978773. and 1007341, this is possible only if

XSS 600 compnent installed on EP7

Please clarify what are the additional steps neede to have this scenario(ECC6.0, EP6 with ESS/MSS 2004)