This Ender 3 modification will not only make your printer a more compact package reducing the width needed, it also improves your extrusion by pulling the filament in a straight line from spool to extruder.
This means that not only will filament not wear the plastic tensioner but the stepper motor is always pulling against similar resistance unlike when there is a big slack loop.
Sometimes its pulling in slack, sometimes it is pulling against a 1kg filament reel. Combined with the lack of resitance from guides, wheels or worn groove gives you a uniform extrusion giving more reliability to your print quality
Aswell as moving the stepper motor and tensioner 90 degrees, there is a connector for cable drag chain build in.
When printing orientate the text side facing up and use supports (zig zag 15%)
Please post makes and pictures