Would like to wire one axis on an analog stick

I have PS3 SFAE sticks that I converted to HAPP parts and six axis controller with axis adapter for wireless. I put Pinball flipper buttons, a X plunger and PS button on the front and sides. The new PS3 pinball game used the analog stick to plunge and the left stick to nudge. So I am looking to mod it by doing an analog switch to activate one axis in one direction. Where would I solder to the board to get the connections? Is it possible? I would like to get down direction on the right stick and down on the left stick.

Right now I have a mod where I reach under the stick to reach the right stick to plunge and nudge is unreachable. I could do a redesign where I clean mount it through the top plexi so I get complete access. Much rather do two analog slider style switches. So any suggestions are surely appreciated. Advice on parts. Also any ideas on how to go about this. Thanks in advance.

You should be able to solder a wire to the trigger pots. You’ll have to test around to see if its the first or third pin of the trigger pot that you need to hook up the signal wire to.

The ground my tester and see which one has juice coming through it when the stick is pulled? That should work right?