If you forget to thread the filament into the MK4 filament guide, you cannot do it later. You must let the filament hang, or use a zip tie or some other temporary fix. Or you could unload the filament but that will take a long time. The added holes in this remixed filament guide can be used whether the filament has been loaded into the printer or not. Problem solved. Otherwise, this filament guide looks completely stock.
The author remixed this model.
The stock MK4 filament guide cannot be used once you load filament into the Nextruder. You can used the slotted holes in this version without unloading the filament.