Enhancing 2LIS_02_SCL

Hi Gurus

I want add field VERKF ( Responsible sales person )in this data source , I am not sure where I need to go. I went to RSA6 and from there display datasource and double clicked on ES MC02M_0SCL then I went to "Go to" in menu bar and there "Append structure" so I am going to enhance ES screen . Am I following the correct path or do I need to populate some exit via CMOD?

Pl help me and tell me the correct process to get this field in this data source.

Thanks a lot in advance.