Nominal Transaction Imports to auto generate the journal numbers as it does when you manually create one

When Journals are entered manually in Sage 200 they auto generate the journal number ie. J00000001 The client has requested the ability to have the system do this for imported journals also. This would ideally consider in the import that the column Transaction Type is flagged as &1& which represents a &New& Transaction and the source column is a &3& which represents &Nominal& therefore a Journal.