Pontiac 2007 G5 Owner's Manual page 310

Headlamp aiming is done with the vehicle's
low-beam headlamps. The high-beam headlamps
will be correctly aimed if the low-beam headlamps
are aimed properly.
The vertical headlamp aiming screws are located
under the hood near the headlamps.
The adjustment screw can be turned with a 6 mm
socket wrench.
310
To adjust the vertical aim on the headlamps, do
the following:
1. Open the hood. See Hood Release on
page 277 for more information.
2. Locate the aim dot on the lens of the
low-beam headlamp.
3. Measure the distance from the ground to the
aim dot on the low-beam headlamp. Record
the distance.