Hello Rick,
The NI-CAN interface is used to program the controller, thus, all you should need is the NI-CAN board and appropriate connections to the controller. In general, this is primarily the CAN high and low lines, which constitute the CAN bus and are used for differential transmission of CAN frames (data). Furthermore, the 56F83xxEVM board contains a CAN termination resistor that can be enabled/disabled via a jumper; termination of this kind is standard on a CAN bus in order to reduce transmission line reflections when communicating at sufficiently high baud rates. You can read more about this in the NI-CAN HW and SW User Manual, which can be viewed and downloaded as a PDF at:
http://www.ni.com/pdf/manuals/370289h.pdf
If you have any more questions
feel free to repost. If you have some general questions about CAN, the user manual linked above is great reference!
Thank you,
JLS