Hi here is a mount i knocked up to allow my new PWM fan control board to be mounted to my printer.

Holes made for 3mm bolts.
Bolts go from below up to attach the board.

Was just something i knocked up not sure if it will help other people out, but here it is.

Link to the item i bought: https://goo.gl/gfHbRh

Print instructions

Print Settings

Printer: Anet A8

Rafts: No

Supports: No

Resolution: 0.2

Infill: 10%

Notes:

top: 3 layer
bottom: 3 layers
shells: 3