They are easy to remove. Unplug the harness (release tab is closest to the switch part itself). A 14mm wrench will undo the locking nut, then just unscrew the switch from the mount.
The switch is then enclosed by two tabs that can be gently pried open with a jewellers screwdriver and then the switch will come apart. Be careful you don't dump the contacts and spring all over the place! It is a simple switch and goes back together easily.
