2000 f150 5.4 with a 98 f250 5.4 installed with 40k on motor, problem is the knock sensor is unplugged because 2000 harness plug is diff from 98 sensor itself the sensor on motor is 3 wire and harness plug is 2 wire? ant suggestions?

 

why not just swap the 2000 sensors onto the 98 engine? You will have to remove the intake manifold to do this but it a very easy job to do.