Installing a new speaker rail fairly simple as it only involves opening the device casing and then removing the broken speaker.
Unscrew the 1.9mm screw located at the top of the device with a Phillips #00 screwdriver.
Unscrew the 2.5mm screw located on the left side of the device with a Phillips #00 screwdriver.
Unscrew the five 2.5mm screws on the back panel with a Phillips #00 screwdriver.
Remove the back panel by lifting it away with your hands.
Use tweezers to unplug the speaker wire from the motherboard by pulling the plug (not the wires) down towards the speaker.
Remove the tape holding speaker wire by peeling it away.
Holding down the speaker rail unscrew the two 2.5mm screws with a Phillips #00 screwdriver.
Remove the speaker rail vertically from the device.