this might help you troubleshoot your problem. it's a pic of my old door lock mechanism.

"A" connects to the "button" you see from the inside of your car that's up when the car is open and down when it's locked.

"B" receives the end that is attached to the key cylinder. i.e. when you turn the key, this white receiver rotates.

"C" gets pulled up when you lift the outside handle

"D" gets pulled when you pull the inside handle

both C & D are pulled by a cable similar to the brakes on a bicycle. in both cases, you can see the part that holds the cable sheath.

I had a look at my passenger door and i think removing the panel would be extremely difficult if not impossible because the dashboard overlaps the door so far.

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