1. Remove the front door unit.
2. Remove the screws, then remove the front door latch and door lock actuator.

3. Install in the reverse order of removal.
Rear door unit removal/installation
Rear door latch and lock actuator removal/installationMazda 6 Service Manual: Limitations to SRS Air Bag
In severe collisions such as those described previously in "SRS Air Bag Deployment
Criteria", the applicable SRS air bag equipment will deploy. However, in some accidents,
the equipment may not deploy depending on the type of collision and its severity.
Limitations to front/near front collision ...
Mazda 6 Service Manual: Front drain hose installation
Caution
If the front drain hose is pinched or bent anywhere, the water in the hose
may not discharge and enter the inside of the vehicle. During and after
installation of the trims and the headliner, always make sure there is no
interference with the front drain hose. Fix any problem if found ...