I used to do contract work with a aviation mechanic who was named Don Adams, he was known as “Agent 86” by everybody on that installation... in fact, I even heard him paged on the intercom “Agent 86 your presence is requested in the admin office”
I think he had been called that ever since “Get Smart” was first broadcast.
Opel GT
In 1969 Season Five, Max switches to a gold Opel GT.
Again, there are at least two, with one being destroyed by errant canon fire from an Armed Baby Carriage from Bunny Beebe's Bye-Bye Baby Buggy Bargain Bazaar on Barnaby Boulevard [Episode #114: "Ironhand"].