There is another super easy possibility: over all blue-grey. In addition to the Dark Green, V-2s from after Dec 21, 1944 were authorized to use over-all RAL 7016 Grau Blau. It would be exceedingly difficult to tell, in a black-and-white photo if a V-2 was Dark Green or Blue Grey.

I highly recommend:

Barber, Murray R, V2 The A4 Rocket: From Peenemunde to Redstone, Crecy Publishing Ltd., Manchester UK 2017

It's a little light on the V-2 in America and non-existent on V-2 in Russia but it is exhaustive on English perspective (as might be expected). Cool color plates and a number of "tail art" drawings from the prototypes.

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NAR 79743
NARTrek Silver
I miss being SAM 062

Awaiting First Launch: Too numerous to count
Finishing: Zooch Saturn V; Alway/Nau BioArcas; Estes Expedition; TLP Standard
Repair/Rescue: Cherokee-D (2); Centuri Nike-Smoke; MX-774
On the Bench: 2650;
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