Seriousl, the M886 look´s in green much better than in red white trim. Magnus , to your questions about the cut outs: even if it is not original to you knowledge, can you prove that this modification never as made somewhere in the Army.
I know about M886 Ambulances of the US Army, which for example are 16 inches higher as the standard. Some troops just added these 40 inches to get a more convenient motor home for exercices. Even to place some injured comrades it is more convenient, when the body is 16 inches higher.
I have seen a lot of vehicles of the US Army in Germany which have NOT been standard but modified to the units needs. Refer to example to US Army 1945 -1995 Von der Besatzungstruppe zur verbündeten Armee, Volume I and II, Flugzeug Publication GmbH or Fahrzeug Profile volume 35 (Units of the US Army in Europe 1981, the divisions and their fighting troops).
Everything is possible and everything is correct until someone can prove that for this special serial nummber the modification is not correct.
It is the same in ANY Army of this world!
Wolf