I've been pretty Lucky in that I have only had to Break Down a Mod once because
e-liquid had gotten inside it.
BTW - Just a Word of Warning: If you do attempt to take the Board out of a Regulated Mod. be Very Careful with the Buttons. Because it can be Very Easy to Break the Button Actuators on some Boards.
And if you do, you now will have a not very efficient Paper Weight.
BTW2 - If the Mod you are doing Surgery on has a Built in Battery, then the Board can be "Hot" in places even if the Mod is Turned Off.
So Don't go poking around with a Metal Dental Pick lifting Wires or trying to get a Mod Button to clear a Button Actuator.
BTW3 - Don't ask me How I found this out in BTW2.