If there is no image found for the account, you can click the "image not found" graphic on the Verify Identity screen to access the Secondary Names screen. On that screen, you may need to uncheck "Photo ID on File" to reveal a "Scan" button. Use this to scan the new ID.
If there is already an image saved and you need to replace it with a newer ID, back up to the "Who are You Serving" screen. From there, access the Secondary Names screen. Then follow the directions above to replace the photo ID.