If you put it on the wall 30 feet in front of the car and you are off
even a fraction of an inch that will translate into being off a very
large amount a quarter mile down an actual road.  I've had the best
luck by just going out on the street at night and aiming the car at
something at least several hundred feet away and adjusting the
headlights to throw the pattern I want.

 Just get the car loaded like you normally drive it, park on a level
slab about 15' back from a flat wall, then measure the center-line of
your headlights.  The pattern on the wall should have the cut-off line
an inch or two lower than the centerline of the headlights, they
should both be at the same level, and the hot-spot should be straight
ahead.

 You can vary the height a little depending on the roads you drive,
but Never put the adjustment above the centerline where the light will
climb with distance - you'll blind people 1/4 mile away.

 American headlights will have a hotter low-beam pattern to the right
than to the left, to light up the curb and merging traffic a little
better, but not oncoming traffic.  Beware of getting European aero or
replacement headlights meant for a RHD nation, the hot spot will be on
the left (wrong) side.  And a smart cop that figures it out will see
the headlight lenses are missing the proper FHMSA (sp?) approval
number and ticket you for unapproved equipment, then you have to fix
it and/or explain it to a Judge.

   --<< Bruce >>--

Just to let you know ...The adjustment went beautifully. Thanks for
your help..
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