Replicating data sources during upgrade of Source system

Dear BW Experts,

We are upgrading our source SAP R/3 system from ECC 5.0 to ECC6.0 but our BW system remains at 7.02.

We have around 90 datasources from the old ECC 5.0 system. During the upgrade, should we in BW replicate all the 90 data sources from the new system and do new transformations to the Infoproviders? Is there a quick way of pointing the existing data sources to the new system since the names of the data sources are going to be the same.

Kindly confirm.

Thanks,

Sai