Hello and welcome to my Mod,

This allows you to Run a Pololu (https://www.pololu.com/product/3786) On the side of of the Fan duct, just requires 2 M2 Screws.

The SKR doesnt have a deicated 12V allways on fan switch so i am using a step down converter and running a signel wire to the negative Cooling fan port on the board.

See my badly drawn wiring diagram in the images, Please follow the terminal names on the PCB and not my Image as Reference.

Recommend this fan: https://www.digikey.com/en/products/detail/mechatronics-fan-group/MH4028H24B1-6-RSR/9962964?

Print model upside down with support enforcer on the PCB side.