Didn't have the notch, but I sometimes use the edge of the insert extractor and the edge of the shotgun extractor as my witness mark. I works as well as the notch, but it isn't as handy or fast.
About half my inserts (einstecklaufs) don't have the locating pins. I just scribe a line across the insert extractor and the shotgun extractor and line em up. Works just as good. A little harder to do in the dark, up in a tree stand