In older cars, I can remember cars from the late 70's, that the temp gauge provided an actual reading.
As indicated above:
"basically they didn't want every commuter idiot that didn't know anything about cars bringing in there car every time they got stuck in traffic and the temps climbed abit."
that the manufactures made the 'upgraded' temp gauge.
Take a look at the MY08 impreza 2.5i. The temp gauge has been replaced by a dummy light that stays on until it reaches safe normal operating temperature.
I do not have an answer, but, I do believe it can be done.