Clutch fan with shroud, good radiator and correct thermostat.
It's all factory so you wont have fitment problems. It's not electrical so you wont have alternator problems.

I spent 3+ hours on the Monday after vannats crawling up the blue mountains at about 5km/h or stationary no dramas. The Mazda 323 in front of my was loosing coolant like it was going out of fashion. I had the above setup with a natrad 3 core.