There is a limit switch on both ends of the headlight bar. One sets the limit for 'up' the other sets the limit for 'down'. Take a close look at the left side of the area, just behind the radiator. Note the headlight "uppy-downy" motor turns a gear that runs the bracket (for the lack of the correct term for this part), which is connected to the headlight bar/assembly.
This bracket physically touches one switch at either end of it's travel.
It may be likely that the limit switch just needs cleaning.
You can contact me directly at Melton01@msn.com
I have images of these parts....
Chuck
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