The 1968 Fisher body manual doesn't have a diagram, but it does have checking procedures for the top. It appears that the only electrical components are the switch and the motor. The center terminal of the switch is the 12v feed, and the other two terminals go to the motor leads. It doesn't mention any wire colors at the switch. It says that the wires at the top motor are dark green, red, and a black ground. When the switch is on the "up" position, the red wire is hot, and when it's in the "down" position, the dark green wire is hot. This just reverses the motor to pump the fluid in two different directions. Just exactly what kind of problem are you having & maybe we can help??