Cadillac 1999 Seville Owner's Manual page 302

A. Horizontal Aiming Screw
B. Vertical Aiming Screw
Start with the horizontal aim. The adjustment screws can be
R
turned with an E8 Torx socket or T15 Torx screwdriver.
Once the horizontal aim is adjusted, then adjust the
vertical aim.
6-38
1. Turn the horizontal aiming screw until the indicator
is lined up with zero.
A. Horizontal Aiming
Screw
C. Indicator
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