Cub Driver wrote:

(iv) Marks may be displayed on an exhibition, antique, or other aircraft in
accordance with 45.22.

Is "antique" a matter of years, and if so how many?

Thirty. See 45.22.b.

George Patterson
This marriage is off to a shaky start. The groom just asked the band to
play "Your cheatin' heart", and the bride just requested "Don't come home
a'drinkin' with lovin' on your mind".