Hole size for Remote door mirror cables

I am adding bullet door mirrors on my 72 Challenger.
The driver side mirror is remote so it needs the hole for the cables to run through.
Right now I have a standard manual chrome mirror and the door does not have the hole for the cables to pass through.
Does anyone know what size hole I need and do you have a pic of the door before the mirror is installed?
Thanks in advance.

Go with the hole size in the gasket?.....

Large eńough to get the joystick throught. Not necesarilly the gasket hole size, since as far I recall you can't remove the gasket from the mirror assembly