Good luck with that!

The Buchons (as well as the Spitfires and Hurricanes) regularly changed markings throughout the course of filming, sometimes every day. One of Robert Rudhall’s books simply shows the art department painting over the Buchon’s numbers with a different colour, depending on what scenes they were filming.

Also, unlike the Spitfires and Hurricanes, the Spanish warbirds were decidedly more uniform in their appearance.