The readings on the two pole are different than the single for the gauge..
The reason to verify the gauge first is that you can then use the gauge to compare the aux sensor temp/ohm chart by using the gauge [ that you now know is accurate] as the base temp..
Then you will know if the acc unit is tripping at proper time
[ when resistance of 2 wire is at correct ohms in reference to the gauge...]

That chart is also in the CD