Buick 2006 LaCrosse - Manual (Page 343)

The vertical headlamp aiming screws are located under
the hood near the headlamps.
The adjustment screw can be turned with a
6 mm male hex.
To adjust the vertical aim on the headlamps, do the
following:
1. Find the aim dot on the lens of the low-beam lamp.
2. Measure the distance from the ground to the aim
dot on the lamp. Record the distance.
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