Justin,
One leg of the fan is directly connected to the negative pole of the battery.
The other leg goes to the radiator switch, then to the fuse #10, then to the positive pole of the battery (via starter solenoid).
http://faq.ninja250.org/images/a/a4/...matic_-_R4.pdf
Your light should be connected in prallel with the fan.
One leg goes in between the fan and switch and the other leg connects to the negative leg of the fan.