Was able to get ahold of a white china marker from the local bookstore so tried that out first.
Pleased with the results, except it didn't really work well for the "gesichert" of the safety. Guessing the marks are not as 'sharp' there so not as much of the marker material fills in there.
Some pics of the results:
http://forum.lugerforum.com/lfupload/tony1.jpg
http://forum.lugerforum.com/lfupload/tony2.jpg
http://forum.lugerforum.com/lfupload/tony3.jpg
http://forum.lugerforum.com/lfupload/tony4.jpg
http://forum.lugerforum.com/lfupload/tony5.jpg
http://forum.lugerforum.com/lfupload/tony6.jpg