This is a new mount for the X axis idler (H wheel as referred in the documentation). It provides for X belt tension adjustment, and sets the idlerl at the same height as the X motor spindle. It butts up against the holders for the two X poles, which take the pressure from the X belt tension.
There is also a small bush to fit inside the H wheel to convert the 5mm hole down to M3 screw diameter.
The mount uses the supplied holder for the H wheel which slides horizontally in the grooves on the new mount. The captive nut is removed, and the bolt goes into the holder and through the 3mm hole in the mount with a couple of M3 nuts to tension the belt and lock it. It requires an extra M3 screw and nut to mount it through the hole in the acryiic slider.
Just updated so that no support should be needed for printing

Ormerod

Doesn't Matter

No

40%

PETG printed at 240/65 for the layer and 230/60 for the remainder

Designed in Open SCAD