Yes, of course. I wasn't thinking too clearly last night.
The USB connector only has four pins.
Still, my reply was successful in bumping the thread.
Now then, would it not be possible just to physically swap over the two small buttons inside the joystick, so that the non-functional one becomes the one you don't use?
I would forget the idea of adding autofire for the time being. That would not be a trivial matter - especially for someone who admits to inexperience with a soldering iron.