After a couple of overheat shut-downs on long print jobs, I needed a main board fan. This fan bracket from NF6X was exactly what I was looking for, but I couldn't find metric standoffs locally, so I just added 16mm spacers to the bracket in FreeCad, with a 1mm chamfer at the base for strength. Printed on my Mini at 0.13125 layer height and 50 percent infill. Then used M3 X 25 screws with lock washers to attach the bracket. The fan is the one recommended in the original, very quiet and stable. My soldering skills are weak, didn't want to risk soldering to the main board, but I managed to extract the contacts from the 12V input plug, loosened the crimps just enough to add the fan leads and tightened the crimp tabs again, then re-inserted the contacts into the plug. Cleaned up the wire arrangement with some more cable ties. After re-assembly, I had to remove the side panel to be sure that the fan was running, its that quiet.