Porsche CARRERA GT-2004 Manual page 171

Floor
The surface upon which the vehicle rests is flat
and approximately level.
Screen
The screen upon which headlamp beams are pro-
jected is perpendicular to the floor and the vehi-
cle's longitudinal axis, flat, uniformly light in color,
unobstructed, and wide and high enough to ac-
commodate the vehicle beam patterns to be
aimed.
The screen should be wide enough to provide at
least 1 m (3.3 ft.) of space outboard of the vehi-
cle's headlamp spacing.
A - Opening for headlight vertical adjustment
Vertical adjustment
The opening A for vertical adjustment is located in
the wheel well in front of the relevant front wheel.
f To adjust the headlights, use a 5 mm Allen key
with a long shaft and ball head.
f turn clockwise = beam moves down
turn counter-clockwise = beam moves up
Note
f Do not alter the lateral adjustment.
171
Practical Tips, Emergency Service