Can I add to this?
I'm at the exact same place. Just hung the engine, and now I find myself in a place I know almost nothing about. Mine is an 8, so if that makes a difference, I apologize for piling on.
I looked through this list (thank you, by the way!) and added three more things, Cabin Heat control, Oil Cooler Valve and Fuel Line. You repeated CHT Cyl 1, so by my count you had 26. I now have 29 penetrations.
In my mind, I have 4 categories:
Mechanical linkages: throttle, mixture, prop, Cabin heat, Oil cooler shutter and alternate air.
Fluid: fuel.
Power lines: Battery, E-mag 1, E-mag 2, Alt 1, Alt 2, Alt 1 Shunt, Alt 2 shunt and Starter.
Sensor lines: Oil Press, Oil Temp, Fuel Flow, Fuel Press, MAP, Tach, EGT 1, 2, 3, 4, and CHT 1, 2, 3, 4.
Fuel is by itself.
Since Power and Sensor do not mix well, that seems like two more penetrations.
Mechanical? I see the Van's holes for throttle/mixture and prop, so that's making me think the mechanical connections have their own penetration, or can they be grouped as well?
Am I kinda, sorta on the right track here?