Difficulty

Part used: NBC-FrontGrill01

Tilt the unit back enough to expose the bottom of the grill.
Locate the 5 screws and the 4 holes below the grill.
Unscrew the 5 visible screws across the metal plate.
Insert the screwdriver through the hole to unscrew from the ceiling of the grill. Then carefully bring screwdriver with the screw out through the entrance hole.
Do this for all 4 holes. If the screw falls and is lost inside the unit, then stand unit upright to allow the screw to fall from the bottom.
When all 9 screws are removed, the grill can slide off freely.
Take the replacement grill and align the slots with the screw holes of unit.
Secure the grill for all 9 locations. Now, you have the new grill is installed.