Rudder cable slots

I've got to cut slots for the rudder cables in both the floorboards and
the rear skins. Are there any tricks for locating the necessary slots
in a way to keep them as small as possible?


--
This is by far the hardest lesson about freedom. It goes against
instinct, and morality, to just sit back and watch people make
mistakes. We want to help them, which means control them and their
decisions, but in doing so we actually hurt them (and ourselves)."