How close is to close?

My buddy runs a hot 340 in his 68 barracuda with the mechanical Mopar offset blade fan with no clutch but runs a shroud with no issues with high rev cavitation as those blades are balanced for less noise and vibration.

The aftermarket3 core radiator might be a struggle getting a shroud positioned properly with a tight seal but I'm sure some ingenuity would get it done right.

I'm gonna try the electric fan set up myself and I posted pics on this forum of my set up.