340 electric fan size?

I imagine you have clearance issues on the engine side of the radiator? If so use two, 11 or 12 inch
fans, put one fan on the engine side a puller and one offset on the other side of the radiator a pusher.
Arrange fans so they cover the maximum radiator area. Forget the shrouds, install relay to
supply enough current, get simple capillary type thermostat for fan temp control, I would not
use a complex electronic type controller I have found them unreliable and expensive.