Typically a CANBus will have 120Ω across CANH and CANL at each of the ends. This gives a measured 60Ω between CANH and CANL (parallel resistors). When the CAN transceiver in a CAN node drives dominant (logic 0) the transceiver provides high and low voltage across the termination resistors.
Using smaller than 120Ω means the total bus resistance would be less than 60Ω, causing the transceivers have to source more current (outside what they are spec'd). So I would stick to 120Ω if you can help it.
For bench top use, if your bus is short (like a couple feet or less) you can probably get away with just one side terminated. But since you are building a bot you should probably not skimp on the bus termination.
If the end of the chain is a PCM you can just insert the resistor into the empty weidmuller pair, like GeeTwo recommends.
If the end of the chain is a Talon you can wire/solder/or use an extra CAN connector to insert the final resistor.
Checkout section 1.3.2 in the Talon's SRX User's Guide for a diagram.
http://www.ctr-electronics.com/talon...ical_resources
Extra CAN connectors...
http://www.ctr-electronics.com/adapt...or-5-pack.html