There are numerous fans avaiable at most parts stores. they all run on 12v usually fed power through a relay. the relay can be powered from several sources--- A/C clutch, Temp switch(newer models) or a toggle switch. most AFTERMARKET fans are "universal" fit and come in several sizes pricing starts about $75 and goes up. Create your own wiring harness, most are designed to "piggy back" an existing system.
******A note of caution*******
Many can be wired as a pusher or puller, depending on which side of the radaitor you mount it on. BE CAREFUL IF THE WIRING IS "REVERSED" YOU CAN CREATE A WORSE OVER HEATING PROBLEM!
I hope this helps, good luck.
Brad
