Possible Clues:

• 6's bird's opposite number
• Referring to a couple of travel documents being short
• With respect to
• In relation to, as compared with
• Incomplete pair of documents for travelling about
• Whichever way you read it it's still relating to this
• Get face to face with this in France
• With regard to two passport stamps: one missing article
• A light carriage with seats facing each other
• Face-to-face, literally