FYI 003,004, and 005 are the MFI '72-73 distributors, with different rev limiting rotors.
008, 009, and 010 are the CIS with different advance curve (i'm guessing about that) but made for CIS, with different rev limiting rotors.
I found out what I know about it looking at old Early S Man threads and here's where that happened:
http://forums.pelicanparts.com/porsche-911-technical-forum/574407-pertronix-008-distributor-again.html