Pontiac 1999 Montana Owner's Manual page 339

7. Replace the new bulb through the black retainer ring
and into the electrical connector. Push the bulb
firmly enough so that the blue tabs hook over the tab
on the bulb.
8. Carefully put the bulb assembly back into the lamp
housing and tighten the black retainer ring in place.
Be careful not to damage the bulb on the headlamp
aiming bar.
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