Siding board/wood

Height: 8" 

Depth (thickness): 6/16". As you noted, 5/16" lands in certain parts of the siding

I have some screw holes already from a failed attempt earlier using shims and the doorbell base plate so I won't note the percentage of coverage. Attached is a photo and the measurements

From the top screw hole to the bottom of the siding board is 10/16"

From the bottom of the siding board to the wiring hole is 3/4"

From the wiring hole to the bottom screw hole is 1 1/8" 

Product details

Google Nest Doorbell Gen3 Wired

Color preference: Black