SAP Upgrade from ECC 5.0 to ECC 6

Hello All,

We are planning for an upgrade from ECC 5 to ECC 6. As some obsolete statements like "Use of header line" is no more supported in ECC 6, do we need to manually change in all custom programs and FMs? Or is there available a tool to do so? or will SAP as part of the upgrade do the necessary. Because this is a huge effort

Thanks in advance for your response

Anirban