I have an 11 year old thermostat model TA-2060 by SECO (Stone Electronics Co). It has mercury tubes and I bought a digital Hunter to replace it with. The diagram provided by Hunter doesn't account for all of my wires, most importantly I can't tell which of 8 wires is the RC wire. The old unit has wires plugged into boxes with the following Letters: W2, O, X, R, Y, G, E, W3. Which is the RC compatible wire and which of my W's is the real W? Ugggh!