Peter; What “cover over the lens” are you referring to???
There is the bellows lens hood/shade but a cover/lens cap???
If you are talking about that front cover with the square hole mask as seen in this photo.
That is either a choke mask to give additional sun shielding when using a longer telephoto lens. (Sun flare was a much greater problem in 1938-45 than it is today with our modern multi-coated lenses designed to greatly reduce flare.)
OR . . . it is a special effects filter. - Shoot one take with the above filter mask. - Then shoot a second take with a filter mask cut to be the reverse of the first. - Sandwich the two films together and you can create, for instance, a close up image of someone surrounded by a background of other moving images, much like a movie double exposure.
Here is a drawing of a possible reverse mask for this special effect.
I had almost the exact same type of tapered bellows lens hood with similar filter masks for shooting special effects wedding shots making double exposures. Sorry, I don’t have a photo of that rig. (My Bronica ETR wedding camera had an override switch that would let you take intentional double exposures.)
Also for the GI’s kit here is a very nicely done map case. I have used a similar one myself to carry film holders. Problem is, it only holds maybe four so with one in the camera that is ten shots total for the day - not enough capacity. The musette bag is really better and more versatile for the job.
As to the question of just how far the lens board and bellows of the “Graflex” should be extended under normal shooting conditions I give you this cartoon illustration from the opening page of the graflex.org historical website:
Have you ever seen the Arriflex battery case in anything other than black?
I seem to remember some sort of woodsy/red leather colored bakelite case but I might be confusing that with some of the German field phone hard cases???
The few photos I have seen of the power pack are B&W so it is hard to tell actual colour but they do seem to be lighter than black. I know the camera itself could be black, very dark grey or a lighter colour depending on where and when it was manufactured (pre-or during WW2 that is).
Have you seen this web page about Horst Grund, a German cameraman. Some wartime pics of the man and his work when you scroll through them (including the one of him and another photographer in the PKW).
Gonna need some film holders for that Graflex:
Missing from the AK offering would be any sign of the film holders needed for the Graflex. (Sort of equal to offering the electric powered Arriflex without including the battery box.)
Wartime film holders would be black bakelite or plastic rather then wood.
The design for either is basically the same.
Four double sided film holders equals eight shots:
Camera, with Flash, Film Holders AND Carry Case would be a nice combo to sell I think. Yeah???
Tripod is another matter - the heavy movie camera tripod is perhaps do-able with 3D printing but the Graflex tripod for the still camera is a spindly little thing that looks as though it might break just under the weight of the Speed Graphic all by itself.
Just 3 leg assemblies and a top-knot that all snap together!
These would all stow in the PH-104 carry case.