Complete closing of Stock Transport Order?

Complete closing of Stock Transport Order?
We use STO for plant to plant transfer.Once GR is completed by receiving plant,the 'delivery complete indicator' is automatically set on the STO line item.If I need to add on STO after the STO is completed,system allows...only shows warning message '06 744 Delivery of item & of document & already completed' and this can Enter through.Our requirement is...block the STO once the GR is completed so no one can change the STO.I think it's similar concept of 'technical completion on a production order'.Is this possible on STO area?Thanks.