Display the second field in a combo box after a selection is made

I have a table that has CustomerNumber as the first field and CustomerName as the second field.

The invoice form has a combo box where the user can enter the customer number. We want the customer number to be displayed in this field. But when the user clicks the drop-down arrow for the combo box, we want the user to be able to type a customer name and have it jump to that customer name as they type. Once they have made a selection, we want the customer number to be displayed in the combo box.

Is there a way to do this? If I make the first visible column in the combo box the customer name, the drop-down typing works fine but the customer name is displayed in the field once a selection is made. If I make the first visible column the customer number, the typing in the drop-down goes by customer number instead of name.

Thanks in advance.