2005 GMC Sierra 1500 Pickup Owner's Manual - Page 457

Headlamps To replace a headlamp bulb, do the following: If your vehicle has one pin on the headlamp assembly, remove the pin. To remove the pin, turn the pin up and pull it out straight out. 1. If your vehicle is equipped with two pins, remove the two pins on the top of the headlamp assembly. To remove the pins, turn the outer pin outward and pull it straight up. To remove the inner pin, turn it in and pull it straight up. 5-63