Primus Finger Pin Decoding
I found a defcon slide that sums up the sidebar heights and offsets from center. If you want to see the rest of the slides there is a reference in the picture.
I then made a graph in excel that then plots distance from the shoulder (taking into account the offsets) and hight from bottom of key.
Ironically, the bottom part of the C1 key fits into the standard primus keyway. I know this because I just made a sidebar setter out of one and it works great! I dont have pics ATM I'll probably post pictures when I'm done with class.