The Edit Orders mod will let you change quantities of products in an order, or delete a product by setting the quantity to '0'. But there have been problems reported when used together with Super Orders. The totals shown in SO do not update automatically. You have to do an 'edit products' in SO and then, without making any changes, do an 'update'. If all you need to do is delete a product from an order, you can split the order in SO and then delete the split order. Of course, that throws off your order numbering system, creating all the deleted orders. and may confuse your customer.