How do you replace the headlight switch on a 1994 Mazda B4000 pickup?

Any Mazda pickup produced AFTER 1993 is a FORD RANGER. If you can find diagrams or instructions for a 1994 Ford Ranger it will be the same as your Mazda. Ford at one time owned a 50% stake in Mazda, and didn't like the competition from Mazda's pickups (much more reliable) so they halted the sale of Mazda's in the U.S. and branded their Ranger pickups with the Mazda name and number designations (B-3000, etc.).