I'm not sure that would work. The engine and fan are too far away from each other. Plus, a tractor couldn't go fast enough to push air thru the radiator if the fan was reversed. The pioneer can go fast enough to over power a reversed fan.
If the fan was directly in front of the engine like a car or tractor, it may work as long as you drive slow.
While on the topic, place a couple bilge fans behind the engine pushing air toward the back of the vehicle and it could create a negative pressure zone under the seat and may help.
Joe