1) Use a small diagonal Pliers trim the up, bottom, left and right as show on the photo, right hand side you may need to trim a bit more to avoid the shell case over press the screen flex cable.
2) Remove the speaker holder (Green Color circle) if not the battery may not able to fit in, cut the left-hand side by measure with the logic board for usb port (Purple Color), Cut and remove the original battery compartment holder (Grey Color), and last trim away the pole or stick on the right-hand side (Orange Color) so it won’t block the speaker.
3) Stick the 3M double side tape to the red color parts, and stick the cover on it
4) Power on and check is the screen work properly, if yes stick the black color double side tape to up and bottom of the screen as show by the photo and stick the screen to the shell case.
5) Fold the screen flex cable as show by the photo
6) Close the shell case and tighten all the screws and you are ready to enjoy your games.