I didn’t find a full tutorial on how to do it, so I decided to post it here. It was my first try and took me about 3 hours last night.
Step 1 – Order a replacement
I started from http://pcsupport.lenovo.com/us/en/products/laptops-and-netbooks/lenovo-y-series-laptops/y50-70-notebook-lenovo/80ej/80ejcto/parts and orderd it at amazon.de
Step 2 – Follow this tutorial
Step 3 – Take some time (a bottle of wine) and go on like this
I marked the places to work on with the blue tools…
Remove the black foil
… and all the way back.