To build a working case.. I first started with MiSTer – Case Universal v5.2 by NegSol on Thingiverse as the base.
https://www.thingiverse.com/thing:2684660
This case design looks like it caters to a straight SDRAM pin layout (better SDRAM speed and reliability) and has enough room for a 25mm Noctua NF-A8 80mm type fan.
Here’s the first go at it.. needs to be a bit taller or the SDRAM won’t fit. Otherwise works great. The fan is powered off the unused GPIO1 pins 11/12 (+5V, GND).
19 Jan 2020 Update – see the white model I’ve printed which is 20mm taller to allow a better fit for RAM, and also the screws don’t interfere with the header pins.
Fusion 360 Model View from the top. Note the heat exhaust from the side vents! Looking into the heatsink.. 42C View from the side showing heat vents