For the 2000 Toyota Tacoma, both the low-beam and high-beam headlights use a 9003 bulb. The supplied fitment data does not identify a projector or non-projector headlight variation, so verify the original bulb before ordering if your truck has a different headlamp assembly.
Other notable exterior fitments include 1156 bulbs for the front and rear turn signals and reverse lights. The brake and tail lights use 1157R bulbs. Center stop and parking light applications are listed with either 168 or 917 bulbs, while the front side marker uses a 168NA.
License plate lighting may use a 194 or 7441 bulb. Interior applications include a 168 or 7441 for the instrument panel, 2721 for the glove box, and DE3022 for the dome light. The courtesy light has two listed options—DE3021 or DE3022—so compare the replacement with the original bulb before purchasing.