For key fob battery replacement, disconnect the cable from the negative terminal of the battery. Remove the steering column covers and use a trim tool to pry off the ignition lock cylinder bezel. Insert the ignition key into the ignition lock cylinder and turn it to the RUN position. Use a pick or small tool to depress the release button in the ignition lock cylinder housing, then pull the ignition lock cylinder out. To install the ignition lock cylinder, ensure the ignition switch is in the RUN position; if not, rotate it accordingly. Insert the ignition lock cylinder into the housing, ensuring it engages with the switch and clicks into place, then verify the ignition switch operates correctly in all positions. Next, remove the steering column covers and the steering wheel, followed by the steering column switches and clockspring. Disconnect the electrical connections to the ignition switch, then use a cold chisel to work the bolts out counterclockwise. Remove the ignition switch housing and install the new one by reversing the removal steps, tightening the new shear-head bolts until the heads snap off. For ignition switches, remove the steering column covers, unscrew and pull the ignition switch from the housing, then disconnect the electrical connector. For keyless ignition, carefully pry off the center dash trim bezel, squeeze the retaining tabs, and remove the switch from the trim bezel, with installation being the reverse of removal.