Hi
You cannot pass an entry unless you know what the differences are. I would suggest the following approach both at company code and account assignment level:
1. Use F.01 to down load the trial balance from system
2. Create an excel sheet with the following details
SAP GL Account No SAP GL Balance Legacy GL No Legacy GL Balance
3. Check the differences where they exist in the excel file and than think of a way to pass the adjustment entry
Thanks & Regards
Sanil Bhandari