In my reseraching I keep noticing that there are different cooling system parts for 1996-1998 and 1999-2000 6.5. Different water pump's are listed as are different fan clutches. What's the difference? Will kennedy's fan clutch work with both water pumps?

The later water pumps have a screw on design for the fan clutch as opposed to the bolt on style. Kennedy's fan clutch only fits the bolt on style. I had to send mine back because it didn't fit.