If you are looking for a load capacity test , just drop the sensor out from the housing and test vent temps..
You could also use this to calibrate where you want a shunt resistor value to get you to.
I would only use metal film, close tolerence resistor for the shunt. They are temp stable [ and 5 for a buck]

Here is a calc to save you some time

http://www.1728.com/resistrs.htm

Assuming you are talking the 2.3, I have specs of 10C at 18.3-21.5 Kohm
and 15C at 15.2-17.2K.
so, you may want see what end of the spread is in there now...you may get away with just another sensor on the other end of the allowable spread.

As stated, a 100K shunt is ballpark for approx. 3k change at these specs