1. Install the clip in the regulator handle.

2. Close the door glass fully and push the regulator handle on as shown.
Regulator handle removalMazda 6 Service Manual: Scheduled Maintenance (U.S.A., Canada, and Puerto Rico)
Follow Schedule 1 if the vehicle is operated mainly where none of the following
conditions (severe driving conditions) apply.
Repeated short-distance driving
Driving in dusty conditions
Driving with extended use of brakes
Driving in areas where salt or other corrosive materials are used
...
Mazda 6 Service Manual: Plastic Part Maintenance
When cleaning the plastic lenses of the lights, do not use gasoline, kerosene,
rectified spirit, paint, thinner, highly acidic detergents, or strongly alkaline
detergents. Otherwise, these chemical agents can discolor or damage the surfaces
resulting in a significant loss in functionalit ...