Hi David!
I checked out my AD 10 and my Evinrude Fleetwin 7.5 and both have a clearly cast in "mark" in
exactly the same place on the cam as you show with the pencil point. I guess yours was just not
"marked" well when it was cast. My throttle follower makes first contact at that point as it
should so I think you would be correct in using your "fuzzy" mark as you have.
C’mon Spring!!
Bob S