Bryant IIT6-WEM-02 Installation Instructions Manual page 15

Installing the optional large backplate
If the small backplate doesn't cover the marks left by the previous
thermostat, attach the larger backplate instead.
Remove the center piece from the small backplate by gently pushing
the snap and pulling toward you.
Insert the center piece into the large backplate, using the tabs on the
right as a guide. It will snap into place when correctly inserted.
Secure the backplate
Drill mounting holes on the pencil marks with a 3/16" drill bit.
Insert the plastic drywall anchors into the wall.
Use the screws provided to secure the backplate to the wall. (See Fig.
7)
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