Communicating with a serial device over XBee

Most of what I know is by reading sample code (I have little formal documentation). I have successfully written/modified code to communicate to the arduino via the XBee to simply read in an analog voltage from A4/A5 of the Arduino. This works well for most of the sensors I have worked with. However, for this application the output from the sensor is already in serial format. I am a bit stuck on how to relay this through the arduino and Xbee.

Reading the buffer from the device directly into Labview (or another serial recorder is trivial). The buffer is simply a set of two numbers (e.g., 141, 121)