Once the back plate is off you will need to detach the frames that hold in the battery. Locate and remove the screws (Screws are marked in the image). You can then pull the frame off with ease once the screws have been removed.

Remove the six 3.5mm Phillips #000 black screws using a securing part of the back panels.

Remove the seven 2.5mm Phillips #000 black screws securing part of the back panels.

Remove the five 2mm Phillips #000 silver screws securing the remaining back panels.