Tevo Tornado Inverted Controller Buck Mount

When I did the first board flip rework on the Tornado controller, I needed to reduce the voltage to the high flow fans I used.
Already restricted for space and having nowhere sensible to mount Buck regulators to control the fans I designed this simple back shell which mounts in place of the BASE PCB under the lid of the Tornado control box and allows 2 commonly found Bucks from Ali Express/Ebay.