What's the trick to removing 1970 Dart wiper switch?

So maybe your dad is at the wrong switch?
That little button described above is on the headlight switch. That knob and stem are formed together, goes in and out of the switch as 1 piece. Its a pull switch. How often would that knob be pulled off if made in the more typical manner? Anyway...
This wiper switch knob once had a small hex set screw hidden in under side. Later model knobs have a tempered steel tooth inside the knob holding it to the stem. I don't know exact year model the set screw was deleted. I do know that little steel tooth could fall out of the knob when the knob is removed from the stem, generating a treasure hunt LOL. and yes both switches have a chrome bezel nut drawing them in place. Counter clockwise force to the notches in the nut should unscrew them. There are special tools for these bezels nuts but most of us get by without. Hope this helps