0FI_GL_21 Missing Chart of Accounts

We are working with 0FI_GL_21 for GL Balances and want to use infoobject 0GL_ACCOUNT which is a compound characteristic with

0CHRT_ACCTS but 0FI_GL_21 does not contain 0CHRT_ACCTS.  The problem is that we have to hardcode 0CHRT_ACCTSin the transformation to display the chart of accounts text

So I am familiar with extending extractors so looked In RSO2 for  0FI_GL_21 and get warning message.

"Data from DataSource 0FI_GL_21 has been extracted using function module FAGL_SREP_GET_BALANCES_***"

ROOSOURCE shows that extractor is FAGL_SREP_GET_BALANCES_***

In reviewing this se37, I don't see the expected way to append the structure FAGL_S_SREP_BALANCES_***

Interested if you have come across with a way to include the chart of accounts in this datasource?

Odd that it is not included, what am I missing

Thanks

Lee Lewis