How do I change the headlight housing on my 1999 lumina

Raise the hood.
Lift the flap on the appropriate end of the radiator upper air deflector.
Separate the radiator side air baffle from the upper air deflector.
Remove the fastener retaining the upper edge of the front bumper fascia to the headlamp bracket.
Remove the two bolts retaining the headlamp assembly to the headlamp bracket.
Slide the headlamp assembly slightly inboard to release the outboard retaining tabs. Carefully pull the upper edge of the front bumper fascia away from the inboard edge of the headlamp assembly enough to aid in headlamp removal. Carefully remove the headlamp assembly from headlamp bracket.