How do you adjust the headlights on a chevy truck?

I have a 1990 chevy scottsdale with the square headlights and i dont have an owners manual....anyone know how to adjust the headlights?How do you adjust the headlights on a chevy truck?under hood where light assembly is accesible there is a spring loaded screw on back of light assembly turn either way to adjust light height. face truck so pointing at a wall to line up light upon it too satisfactory adjustmentsHow do you adjust the headlights on a chevy truck?their should be a screw in the middle above the light inbetween the light covering maybe you will need a star bit screw driver for it dont loosen or over tighten you should ajust it at night to be shure where it is shinning at.