WMS Rule to select our parts in multiples of 40 (pallet size) without using LPNs

Hi Gurus

We have the following requirement, when a sales order quantity is 130, we want to allocate (3*40 (the pallet size) to the PALLET subinventory and back order the remaining 10 WITHOUT using LPNs.

We are currently using LPNs to achieve this requirement but the warehouse does not want to pack in pallet any more, it is too much work.

I have read the Oracle Warehouse Management, Rules Engine Examples upside down but I cannot find a way to allocate or putaway a transaction  quantity based on mutiples.

I am trying to do a simple picking rule that would allocate the 130 and then may be a putaway rule that would only putaway 120 and backorder the rest but have not found a solution.