Here is my short term solution to coolant temp. All it takes is a Wireless OBD2 like this one , Four Stroke for iPhone with the $3.99 upgrade to gauges and an old iPhone. The OBD2 times out if you dont' plug it in each time you start the car, but it works for now.

 

I've been doing the same thing for the past two years using the Torque App on Android with a suction mount phone holder.

 

Very cool! Thanks!