To change the tail/turn signal lamp (not stepside), make sure that the headlamp switch has been turned off and lowered the end gate. Remove the two screws that hold tail/turn signal lamp assembly to the body; then find the changed bulb: the highest bulb is used as a parking lamp and stop lamp and the middle bulb is used as a turn indicator lamp while the lower one is used as a back up lamp. Then, twist the socket assembly away from the housing. To install, rotate the socket and secure it back and re-install the tail/turn signal lamp assembly with 2 screws. Lastly, close the end gate and check the work.