Year End Close - Deleting Period 0 data for operating unit

Hello,

Our business users are requesting to delete data for a specific operating unit for period 0 on certain years.  The reason that they have requested to delete this data is that we have sold that company and the company had a balance of -0.02 on one asset account and 0.03 balance on another asset account back in 2009.  We have inactivated that operating unit however these balances continue to roll forward due to the year end processing at a business unit level.  We have huge concerns about deleting the data as we are not sure which tables we should delete