This is a remix where the extruder is rotated 90 degrees so that the weight is closer to the x-axis carriage, while still having clearance to the frame not losing any z-axis.

The stepper motor spacer is the same as with the original adapter. The adapter needs 2x 20mm m3-screws like the original.

Update v2:
The old design allowed for the extruder to flex a bit when the filament doesn't feed perfectly. This new version now has a front plate connected to the base with 2x countersunk M6x8 screws (left over IKEA screws). It works with the original screws/nuts for the wheels.
The base comes as two types. One with a pilot hole to drill for the cable chain, and one with a cable clip. A one piece version, as well as the first version is also available.

Extras:
Cable chain - https://www.thingiverse.com/thing:4543675
Longer extruder knob - https://www.thingiverse.com/thing:4547854