I couldn't replace just the bulb. You have to buy a whole new lamp. $5-10 at autozone.
REPLACE THE PASS SIDE HEADLIGHT
Open the hood of the engine compartment to your 1994 Toyota Corolla. Remove the wiring harness from the headlight. Remove the headlight retraining bolts from the headlight assembly. Reverse the process to install the new headlight.
detach the bulbs and remove the clips behind the headlight assembly
Lower the steering column.
replace the headlight switch its wore out replace the headlight switch its wore out
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.).
800.00 to1100.00 used
heater core removal
For the 1994 model (B3000), you can't change just the bulb. You have to change the headlight assembly.
for a 1994 Grand Caravan (probably like the 1995) see: How do you replace the headlight assembly located on a 1994 Dodge Caravan? for a 1994 Grand Caravan (probably like the 1995) see: How do you replace the headlight assembly located on a 1994 Dodge Caravan?