With the following steps we will be switching the feeder idler drive arm for a custom version that has been optimized for 1.75mm filament.
a) Fully loosen the tension on the extruder spring to ensure that when the extruder casing is removed it does not pop out.
b) Remove the extruder casing by unscrewing the 4 screws securing it. Take care to keep the pieces in the same place internally. Gently remove the white drive arm from the assembly.
c) Slide the provided black aluminum drive arm into the assembly in place of the one you just removed. Remove the metal eyelet and store it in a safe place, you will not need it when using this 1.75mm drive arm. Reinstall any other components which may have fallen out or moved out of place. The internals should look like the photo below before adding the top casing back.
d) Reassemble the top cover by tightening the 4 screws.
Tighten the idler arm spring tensioner to ½ using the tension indicator on the right side of the filament feeder.