Another poster gave this reference "from gen2 service manual)
the sensor is located on the driver side next to the front windshield vent on my gen2.
12. ADJUST AUTOMATIC LIGHT CONTROL SENSOR
(a) Adjustment of the light control is performed by turning the
sensitivity knob on the sensor.
(b) This will be determined at what light condition the automatic
control will take place.
If response is too quick, turn the knob counterclockwise.
If response is too slow, turn the knob clockwise