OK, edited my post above will all the nasty sausage making details of my adventure in film conversion.

A bit of additional news:
Besides the short clips of RAF Spitfires and Halifax’s (yes, with black underbellies), there is a 4 second clip of an Farman F.2200 F-AOXE!!
One of only 4 F.2200, this is quite a find. I think it is Algiers, and pretty certain it is 1943!

A pic I found on net.
https://www.edcoatescollection.com/ac5/ROW%20Europe/F-AOXE%20Farman%202200.jpg