Pretty much every switch that has a pull knob made since the 50s has a release like this on the switch behind the dash. Take all of your jewelry off and feel around for a button that looks something like this.
push it and the knob will come out. Then turn the chrome bezel. Be aware that this will also turn on the lights. I guess I should have told you to unhook the battery. I never do but I have done this a few thousand times.
All you have to do is push the knob back in and it will catch.