SD Process Design for Plantation industry - need advise

Hi all experts,

I am implementing for a crude palm oil plantation company, in which the general flow of the sales process from Estate to the Milling Plant is as below:

Sales Order --> Delivery Order* --> PGI --> Billing*

Sales Order: The fresh fruit bunches (FFB) is harvested and then the amount required by the Buyer is fulfilled via creation of a sales order.

Delivery Order: At this stage, it will interface with the Weighbridge system to carry out the recording of delivery quantity. Truck without the FFB is weighed once at entrance of the estate, and truck with FFB is weighed at exit at estate.

PGI: Goods Issue is carried out with the recording of the actual quantity from the weighbridge interface back to SAP.

Billing: The billing doc is created based on PGI quantity done.

This looks pretty straightforward, but there are few concerns from the above process as highlighted in the asterisk (*) section:

Issues:

1. During the Delivery portion, data of the Driver, name, person loading and weight loaded need to be recorded at the same time to carry out the incentive payment to the drivers (both internal and external drivers) with incentives calculated on per tonnage basis.

2. Secondly, during Billing process, the amount payable would be calculated based on the grading of the FFB + the which year the FFB is planted (i.e. different year would have different pricing per ton).

Need advise on how to make the above two issues work smoothly along with the process above.

Opinion, comments and feedbacks is much appreciated.

Thanks.