For RAPID cooldown;
An electric H2o pump and a 110Volt cooling fan and/or a garden sprayer tank with H2o sprayed directly on the radiator with the electric H2o pump running.
Now to your question;
A 'puller' with a proper and tight shroud is more effective as you'll be drawing air through at least 90% of the radiator. 'Pushers' only cool the area directly in the path of the fan blade, nothing outside that circle.