I was looking for a way to attach a rear light under the saddle on my MTB. Found https://www.thingiverse.com/thing:857803 excellent as I had the same taillight.

Remixed this on for my new light by changing the light mount dimensions and also "dragged" the saddle mount a bit outwards and rotate them a bit for better clutch.

Oh and add also two holes for zipties to make it MTB proof.

An Bambulab can print it without supports but definitely better results with support.

Bambulabs

Yes