This is a modified Version of my Cycle Analyst V3 holder matching a KT (Kuteng) LCD8H. I guess from the distances of the screw holes this should fit a LCD3 as well (older display version).

There is a notch for the cable output on the back of the display. So the included STLs are for right-sided mount of the holder. For left-sided mount of the stem you will have to adjust the OpenSCAD file accordingly.

STL files are included for 31 and 22 mm handlebar diameters. This should fit for most straight bike MTB handle bars.

Edit: I did a re-upload for the 22 mm STL since I rendered it with 31.8 mm diameter as well. Sorry..... :-(

I used M4x30 mm screws with self-securing nuts.