40mm Fan Duct for Anycubic Kossel with Trigorilla for TMC2130 stepper drivers

I originally used Facocero's fan duct, the 'Dig Dissipator' edition.
At first I thought it worked OK, but later found that it seemed insufficient. The drivers still overheated and shutdown.

I felt a key issue with Facocero's design was that the fan could move air around below the pcb, and that would be an easier path, and waste a lot of the air movement the fan creates, instead of sending it through the duct.

Additionally, as I have TMC2130 drivers I needed to use the SPI pins, and so needed slots for these to be connected.

Since I'm no good at modifying original STL files I instead decided to re-create his work, and design a new fan duct in a similar style. My new duct takes a 40x40 fan, and provides spaces for my SPI cables. The new duct perfect fits my fan, to the point that I could probably not bother with screws at all, and also ensures all airflow created by the fan pushes air through the duct.

After trying a few fans I settled on the Noctua 4020 fan, it's e