This is a quick guide on how to replace the Rear I/O LEDs.
You should see something to this effect.
There are 3 metal tabs that are holding the wire in and the LED clip that holds the LEDS in place. Most of the time the wire will slide out of the tabs with a little effort, and the LED holder just need to move one tab for the LEDs to come out.
Do that same to the upper LED and this part is done.
Install in reverse and you are all set.