Barbara - I don't know how to go any further. I don't know what training a Special Forces Officer would have had and I don't know if the use of the grid was esential training for all men. So I guess get in touch with your friend to see what he knows and what he has. I suspect that the "protractor" might have been Army issue and would not have been included in the material a soldier would be entitled to. However your friend should know. I'm sure you could do it if you had all the equipment.
If the men could do it when under fire with so much depending on it I'm sure ordinary people could with quiet surroudings, etc.
You need to have the exact map they put the overlays on. If you do get them they will probably not be transparencies so you would need a bit of ingenuity there.
I do not know if all the services used Michelin maps. If they did modern maps are much the sams as for distance if you get the proper size. The maps Don had were 1 centameter = 10 kilometers. And I think that can be had in a modern map. And it seems to me the whole army must have had the same maps since they had to work with each other. Hope you can make it work, Mary