Dear Engineers and Experts, 
I have found a very nice enclosure to contain my air monitor and sensors.
The only drawback of it is - there is a large opening (perhaps for ethernet) which is redundant for my design.
So, could you suggest a way to cover or patch this rectangular hole (inside the blue lines) so my end-users cannot see or touch the electronics inside?
The manufacturer claims that this enclosure is made from ABS plastic.
Tooling I have - a Bosch Dremel 3000 mini drill with wheel cutters, a mini table vice. 
