Check this site out.

http://home.att.net/~jbaugher/1942_5.html

42-102940 to RAF as Fortress III HB789
42-102941 to RAF as Fortress III HB790

Both SOC Mar 11, 1947.

They may have had the same Code letter, at different times.

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Many many thanks indeed Vern ,

Most helpful mate !!!!!!!!!!

Cheers 😎

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