I got Adafruit's RTD amp and got it wired up. I tested it just for a couple of minutes and it wasn't reading. I think I have the wiring reversed--there should be 2 grounds and 1 lead, but I think I got it reversed. Adafruit's instructions say to put the two matched wires on the + terminals but for this RTD I'm suspecting I need to connect them to GND. In any case, I won't have more time to play with this for a few days.