Oil temp gauge + source of switched 12V in the 147 - info
Finally installed Oil temp gauge! While installing it I have found good and very available source of switched (over the key) electricity if somebody needs it for some other purposes.
Oil temp gauge was bought with all fittings and sensors, and with mounting cup. I have decided to install it on A-pillar because I like that position, it gives sporty look to the car. Maybe somebody will find this to give "rice boy" look, but I was not able to find better position in 147 cockpit, especially if didn't want to destroy cockpit. Also this position was easiest to work with.
Searching for the best position to the sensor was difficult, and I have decided to put it near to the oil filter. 2.0 engines have 2 screws (see pics) because this blocks were also used for turbo charged Fiat engines (I think), and in that place can be installed oil cooler. Lower screw is for oil flow from pump to oil filter, and upper is going back to engine. I have decided to use lower one because it gives better info about oil temp, the oil is not cooled.
Readings received from the sensors are: 100+5 deg.C for normal use, 105 to 110 for "spirited" driving, and 115 while maintaining speeds near max on highway. As expected, oil temp needs 4-8 min more than water temp to reach normal position.
About electricity: while searching for switched electricity (means that has power only when key is in the ignition), I have found that easiest place is to remove gear lever boot (very easy, just dive with one finger in front part of boot and disengage front tooth from inside, others will come off easy), than reach with two finger under cigarette lighter, and disengage connector by pulling it down while pressing tooth with inside finger.
Wires are: green-black strong wire is ground, white-red strong wire is switched 12 V, and yellow-green small wire is light for cigarette lighter (has 12 V when position lights are ON).
I hope this info will be useful for somebody else too!