Morning, it's been a while but from memory apart from being a pain in the arse a recall it being left, if I'm wrong I apologise in advance and sure someone will correct me, I nearly gave up!! :lol:
It's a normal right-hand thread. To remove/install it with engine in place, I put a 36 mm socket on the nut with a longish breaker bar and let the bar wedge itself
somewhere back there while I turn the shaft by means of the inner (front) alt/gen pulley half. Works well if the fan nut is not all rusted solid.