Migrating portal from 6.0 to 7.0 - ESS/MSS

Hi,

We are planning to upgrade Portal from 6.0 to 7.0 along with ECC to 6.0. We have many customization done in ESS/MSS and we want to keep the same customization in the newer version of portal. Can you please let us know how to achieve this ? I know that we need to be in synch with ECC version for ESS/MSS, so we are upgrading BP for ESS/MSS as well.

Thanks,

Vinit