Sliced with Prusa slicer 0.2mm for all layers with a brim - takes around 50 minutes on my printer - the original upload did not have a flat base - the GS208V2 bracket reworked2.stl file now does - original deleted
I have added a magnetic version that requires 3 10x10mm cylindrical neodymium magnets - print with the 3 cubes on the print bed and apply tree supports - it needs a lot. Pause at a suitable layer ( 62 on my settings ) to insert magnets then resume.

ELEGOO

ELEGOO NEPTUNE 3 Plus

Doesn't Matter

Doesn't Matter

0.2

100

printer is Neptune 4 - not in the list - printed bracket works but could be a little deeper and have a higher front arch

Three strong magnets allow the router to be attached to a suitable metal surface such as a filing cabinet