Max,
I just obtained my first luger, a 1918 DWM, a week ago. The seller stated that the grips were not numbered, but on examination under a lighted magnifying glass I found matching numbers on both gtips (Oh joy!). They are about 2.5mm high, upright on the grips and approximately centered. They are lightly struck. I've included a picture of the Left grip number taken with strong side lighting.
Vern
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