Buick 2004 LeSabre Owner's Manual page 289

Notice: Do not cover a headlamp to improve beam
cut-off when aiming. Covering a headlamp may
cause excessive heat build-up which may cause
damage to the headlamp.
The top edge of the cut-off should be positioned at
the bottom edge of the horizontal tape line.
6. Repeat Steps 4 and 5 for the opposite headlamp.
5. Turn the vertical aiming
screw (C) until the
headlamp beam
is aimed to the
horizontal tape line.
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