How to enhance open Item data source from R/3 ??

Hello All,

I am trying to enhance the business content extractor for open items in R/3 . The data source is 0FC_OP_01. i know this is coming from the table DFKKOP.

I need to add sub GL ffield rom another table from DFKKOPK .

Please advise the step by step to enhance the existing structure and add the new field to the extractor.

Points will be rewarded for any helpful answers.

thanks in advance,

AG..