Yeah flat head screwdriver to slightly prise the plastic housing out above your head, then pull i out.. Should all fall out with wires attached to each part, Find the black tube that houses the small fan, Unclip that from the grey main housing, And unclip it from the wiring loom..
Unclip the fan tube from the rotor blade, Pull it off and clean the gunk off, Oil it up.
Hard to explain because it explains itself if you can use a screwdriver.