A case for the NVidia Shield Pro 2019, with support for a 40x10mm 5V fan.
My original fan decided to make some angry noises and I went looking for a replacement fan.
A fan is ~45 EUR + transport so...here we are.

Hardware needed
A functional NVidia Shield Pro 2019.
A 40x10mm 5V fan. I recommend NF-A4x10 5V PWM from Noctua.
4 M3x12 bolts for the lid.
4 M3x20 bolts for the fan.

You can re-use 3 of the original screws for the mainboard.

Fan setup
You can run the fan at normal or slower speeds, depending on what you are doing with the device/how hot it might get.

Cut the cable from the old original fan as close to the fan so you get a longer cable.
Splice it with the cables from the new fan like so:

Lower noise, higher temperatures:
Shield - Fan
Red - Yellow
Black - Black
Yellow - Green
Blue - Blue

A bit more noise, lower temperature:
Shield - Fan
Red - Yellow
Black - Black
Yellow - Blue
Blue - Green

Or, use a ready made adapter like this one: https://www.adafruit.com/product/4209

Please note that the fan will not start as soon as you power up the device and will take a while to start spinning. 
Play some 4K video to make it start faster.


Printing
I have used HT-PLA from Polymaker for its higher thermal resistance.
Make sure to remove supports from the vent holes on the side and only have supports for the port cutouts.
Supports for the lid are easily removed by inserting a small screwdriver (max 3mm diameter) and pushing from the bottom of the lid towards the top.