I'm terrible at soldering but still managed to do this repair.
Left joystick was really wobbly (stick jiggled a lot without sending any input) and would also sometimes drift with no user input.
I'm terrible at soldering so it took about 40 minutes to get the joystick module off the PCB. At about the 30 minute mark I started using flux and it made desoldering so much easier. The guide doesn't talk about it but I highly recommend using flux to solder/desolder.
Use flux! (After you have finished, use some iso-propyl alcohol and a short-bristled brush to remove the flux residue)