I do have electric on my mild 318, but I wouldn't even think about electric with a big block. (Need so much CFM) that the power draw would be knarly.
I ran and had issues with a 440 in my Roadrunner and this is my own best oppinion of what works well with them reliably.
Clutch fan
Good radiator
Shroud
I used a solid a flex fan and a clutch fan all three at one time or another.
The soild fan pulled the waterpump shaft out of the pump at 5400 R's twice.
The flex fan had less CFM and still got hot.
Clutch fan and a shroud never had another problem with it.