Rodger, how did you put a temp sensor in line?
I have never heard of the SPA gauge Planenut. Will check it out.
When I have connected with protune, one of the measurements was temperature. I am surprised there is no way to access that reading without hooking up to the USB port.
the easiest way is to get a brass three way fitting (female) and put two nipple adapters, cut out a section of return hose and fit this there. I used a oil temp sensor/gauge I got from summit racing and with step down adapters this went into the third hole