As a point of interest is that during WWII my father was a production manager on the A-20 Havoc line at Santa Monica, CA. I once inquired to him as to how they kept the markings, paint schemes and stenciled nomenclature organized on the aircraft going to the various lend-lease nations. He commented that it was quite easy. All the A-20's coming off the line were finished in std USAAF markings & insignia "per the contract". A modification center had been established at Barstow, CA for the Lend-Lease A/C where the US insignia was painted over with new insignia and maintenance /service manuals in the proper language were placed aboard. They were then flown off to their ultimate destinations. North American Aviation modified lend-lease A/C there too.
They chose not to do the mod work at the factory site because the workers were all unskilled people ( senior citizens, people unfit for military service, housewives, etc) doing simple assembly operations (like you see on the auto production lines) so they did not wish to confuse the people. The goal was to produce an A-20 every two hours! Do not jeopardize the schedule!!!
BTW, I drove past Barstow airport a few years ago and the wooden WWII era modification center barns were still there!!
JDV
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