The stock gift that was used to pay the pledge should be credited the amount of the pledge payment.

The stock gift created for the overpayment of the pledge should be credited for the sale price of the certificate less the amount already applied to the pledge.

When selling the stock gift, the profit and/or loss of the sale and the commission should either be (as) distributed proportionally between the stock gift that was used to pay the pledge and the overpayment stock gift or (b) placed entirely on the stock gift that was used to pay the pledge or the overpayment stock gift. 

For more information on overpaying a pledge, please see BB78441.