First of all - Thanks to uwearzt!
Also thanks for sharing the Fusion360-File. This helped a ton!
I modified his nice, minimalistic Din-Mount for the Pi4 / Pi5 a bit to use my M3 rivet nuts to fix the Pi4 without any Spacers and other stuff. Only four M3x10 screws - done.
I printed it in PETG with little support in the overhangs (holes for the rivet nuts), which are really easy to remove.
One Note:
To mount the Pi I had to enlarge the holes by 0,5mm. I simply tapped through the existing ones, which still have more than enough clearance for the screws without touching any electronics, as you can see on the picture.
maybe one time i edit this for the usually used 2.5mm screws (simply modifying the width of the holes) to use rivet nuts but at the moment i just don't have any, so i made it work that way. anyway i am pretty happy how this turned out and i'll use it as is.
hope this is useful for someone else.
cheers! and happy printing!
The author remixed this model.
changed the holes to use rivet nuts