How do you replace a headlight switch on a 1970 Buick Electra?

To replace the headlight switch on a 1970 Buick Electra, first disconnect the battery to ensure safety. Remove the dashboard trim panel to access the switch, then unscrew and disconnect the wiring harness from the old switch. Install the new headlight switch by connecting the wiring harness and securing it with screws before reassembling the dashboard trim and reconnecting the battery. Test the new switch to ensure it functions properly.