Here is how I got it to work in I²C Mode:
- Follow the instructions by Netoperz, big thanks!
(I used the big GND pad on the bottom to heat up the chip with a soldering iron and later resoldered it with the help of a lighter
).
All there was left to do then was to figure out, which pins are SDA / SCL.
Looking at the Pinout of the chip found in the datasheet it is quite clear:
Fortunately for us, these pins are already on the header!
I²C : Board -> Pin on an Arduino Nano / Uno
SDA : SDA -> A4
SCL : MISO -> A5
With the EA Pin left floating the address seems to be 0x3C.
Connecting it to GND (via resistor) causes the address to change "randomly" between power-cycles.
This should MUST obviously be avoided. Currently I haven't changed anything besides what Netoperz showed in his image.
Maybe connecting the I²C address pins would be a good idea... 
My other photos:
I2C_Scanner_BEST.ino (2.17 KB)