Only just found out it might be wrong
I just checked the resistance with a multimeter on a original controller and a gamecube wii classic knockoff.
between 3v and resistance line I get around 7k ohm when not pressed and 450 ohm when pressed. However it's the opposite between ground and resistance. That would mean wiring it like I said on with the 3v line is not possible as you can't reduce ohm's that way. Maybe wiring it to ground would be a better solution. I'm going to the shops tomorrow and get some resistors and play around with it.
I also have a trustpad wii classic controller which doesn't have analog shoulder buttons. I'll ahve a look inside and see how they did it. As for the classic knock off it was 5k ohm no pressed and 200 ohm when pressed. I doubt it'll make much of a difference but then again some controllers can be picky.
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