This is a mount I designed for my Garmin 396-LMT-S GPS unit so it fits neatly on top of my dash.

Print it in PETG or ABS (profiles included) so can withstand outside temperatures.

Printed it in PETG-CF myself and it looks great!

Use 4 M4x30mm bolts and (nylock)nuts

I also made an Anti Theft add-on for this GPS mount. You can find that here: https://makerworld.com/en/models/398130

Pro tip: put a piece of thin double sided tape around the bar before mounting the brackets so it will never slide out of place.