Vauxhall Corsa Owner's Manual page 191

Fit the tail lights
First remove the rear (1), then the front (2)
tail light from the recesses.
Open out the bulb holder on the back of
the tail light all the way.
Driving and operation
Push the clamping lever down and push
the bulb holder into the retainer until it hits
the stop.
Perform this procedure for both tail lights.
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