Yamaha RHINO YXR66FSEW Owner's Manual page 398

7. Install the bulb holder by pushing it in and
turning it clockwise.
8. Install the bulb holder cover and the cover at
the rear of the headlight.
CAUTION:
Make sure the headlight bulb holder cover is
securely fitted over the bulb holder and seated
properly.
9. Close the hood.
10. Adjust the headlight beam if necessary.
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