1996 0lds 88 Lighting sentinel repair

My photocell has become so sensitive it turns the lights off if I drive under parking lot lights and won't turn the lights on in the evening until the sky is almost dark. Same thing in the morning I have to turn my lights on manualy as they won't come on by themselves if there is even a slight bit of light in the morning sky. Anyone out there who could tell me how to change out the photo cell? Thanks, Rick.