Simple enough. Message an admin and request to be able to edit the thread, which should let you change the title.
As an alternative, you may be able to have it inspected and recertified as a truck or van, with the seats removed.
I have read some tidbits about going through Vermont, perhaps it is easier there?
"Cheese Wagon" <email@example.com>
Former owner - 1989 Ford B700 64-pass Blue Bird (Rest In Peace, Cheese Wagon)