I am trying to plot seven 6 figure grid references that plot an area designated as a neutral zone during WWII (Belsen 1945). The grids can be plotted on G.S.G.S. 4416 sheets M4 and N4, I believe dated 1943 of which I have a very small print of. Unfortunetly I cannot read the projection used or anything that will help me plot these grids on a modern map/google earth. Any help with conversion would be greatly appreciated!