No need to buy additional screws. I could attach both of the backplate and the cooler just with screws provided by Cooler Master.
I put all these in my garage, and for the internet connection, installed a WiFi multi-bridge, which transparently connects the Raspberry Pi in the garage to the Verizon WiFi router in the living room. My garage is crazy cold these days so my chilis show about 38GHs at below 60 Celsius degree.