Yes, Imageshack delete the images...

Take a look in this topic, is described the "Bic HALL pot" idea.

http://SimHQ.com/forum/ubbthreads.php/topics/3225807/DIY_hall_sensor.html

Just don't get the HALL sensor used by OP, has low sensitivity, get:

Allegro A1324 EUA-T or
Honeywheel SS495A1.

But if you look back in this (MMjoy2) topic will see some "HALL pot" in CH joysticks.

Ideally you should install bearings in gimbal pivots, for minimize lateral play - CH gimbal has lot o play, but as the pot axis pole* is part of gimbal, no big issue for pot use.

* You need keep this axis pole, or gimbal will fall apart.

AFAIK - Back in the topic ate a CH Flightstick with bearings installed in gimbal.