Overheating 360 new engine

Get rid of the toy fans.

Factory clutch fan with Hayden or similar severe duty clutch; matching shroud, blade tips close to shroud. If this gap is to large, the shroud becomes useless. Seal up shroud to rad gaps; & seal up rad to rad panel. Idea is that ALL the air should be pulled through the rad core, not through other gaps.
If you have a good quality alum rad, it dissipates heat better than copper/brass even though copper is a better heat conductor than alum. Reason for this is the large 1" tubes used in alum rads; they allow for a more efficient fin shape to be used & the fins are what dissipate the heat.
Another veeeeeeeeeeeery important point. i would like a $ for very car that I have improved the cooling on. The pump impeller should be closed off if possible. Any gaps means that the water is just splashed around, NOT captured to be pumped through the engine. Each blade section of the impeller should act like a scoop that has two sides....I often weld 'donuts', a metal plate to the impeller to make the scoop.
Use as much initial timing as possible. It makes the engine more efficient; when the engine doesn't have to work as hard, it runs cooler.