1. That was the way the "on safe" position was indicated on the early Lugers, Models 1900 and 1906 (there were some 1906 pieces with GESICHERT marking - rare)
2. No. The mismarking is almost assuredly a restorers error.

Eric - a wild shot here, but look on the back side (inside) of the sideplate on the 1900 and see if there are any intials stamped there....like GCM?

Doug:

Hey!

I think Ron will agree the stamp on the right side of the takedown lever just isn't the right font or size, in addition to being a mis-stamp and in the wrong location. The gun also exhibits several other clear indicators it is restored such as the partial remaining blue in the safety area.

Clark