Refer to the exhibit.

Update the SIP profile on the SIP trunk by checking “enable external presentation name and number”

Change the calling line ID presentation on the SIP trunk to allow.

Create a calling party transformation patter that matches the desired directory number and add a mask to modify the calling number

Create a called party transformation pattern that matches the desired directory number and add a mask to modify the calling number

Add a calling party transformation CSS to the SIP trunk.