Closed subledger transaction migration from 11i instance to another

 We are in the process of developing a strategy for migrating Apps data from an existing 11i instance to another. The target instance already has around 15 SOBs and many OUs. The modules are - AP, AR, GL, CM, FA and iExpenses. The business users want the historical transactions in the existing application migrated to the new application as is. We had suggested migrating only the open transactions in the subledgers, but citing statutory requirement of keeping 8 years data, they want the historical data as well in the new instance. One of the approaches we are thinking is to