Prusa Research MMU3 Manual Del Usuario página 91

PASO 5 X-carriage-back disassembly
Cut and remove all the zip ties on the cable holder behind the extruder.
Release the textile sleeve on the cable bundle by pulling it back slightly. Usually,
there is no need to remove it completely.
Remove all four M3x10 screws on the X-carriage-back part.
Split the x-carriage about 10 mm (0.4 inch) apart in the back to ensure the cables
will be able move through more easily.
PASO 6 Desmontaje del ventilador del hotend y FS-cover
Release and remove the M3x10 screw on top.
Remove the FS-cover. It will be replaced with a new one.
Release the M3x40 Idler tension screw with the spring on the side. You can leave it
in place.
Release the M2x8 screw, unplug and remove the IR filament sensor.
Be careful with the IR filament sensor, hold it by its sides. Try not touching the
components on the PCB. Keep it in an ESD-safe place.
Release both M3x40 screws on the front, just few turns to create about 0.5cm
(0.2inch) gap in the extruder body.
Release and remove all screws holding the Hotend fan on the side. Remove the fan.
We need to reach a screw behind the fan.
9B. Mod extrusor MK3S+ (KIT)
Ensamblaje Original Prusa MMU3 91