Inventory Location: Can this be set at header/body level?

Hi All -

BACKGROUND / CONFIG - Currently our account is configured as 'always allow per line classifications on journal' = T.  We also have location as both a body field and a column field on our sales orders and purchase orders. We use multiple inventory locations to manage our Retail (Location: Retail) and Wholesale (Location: Wholesale) inventory, so we have quantity of most items in both locations. 

QUESTION - I would ideally like location to be specified at the body level and then to have that location apply to all line items and not require staff to set the location with each item they add to an order.   I am referring specifically to inventory locations as in the location to/from which item quantities are received/fulfilled - not necessarily for reporting/classification purposes.