Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:3506958.
You can buy the fan I used here: https://amzn.to/2CuSAPj - Though I did cut the wires and solder them shorter to have less of a mess on my head.
Wanted something that was small and easy to remove. Most other solutions involved attached something to the whole headset but considering the light weight of the fan figured why not just use the USB port to support, it is a full size A after all.
I suppose this could work even if you didn't have the Pro, you would just plug the fan into the usb out on the headset.
Note. I also turned around the fan grill. Since there's a gap between the fan and the unit it seems to make more sense to blow on it then to suck, so I put the grill on the back to protect getting my fingers nicked.
Results? after an hour I used to have 80-90C with lots of gray screens and reconnecting. now with the fan on Low I get about 60C which stops all the issue and I can't hear it with the ear cups down even if the game has no audio. Setting to high will drop it down to 40C but you will hear the noise even through the headset.