The power button, power LED, and hard drive LED are all within a plastic "chasis".
There is a zip tie holding the wires/cables for the front connectivity center and front power button/LEDs. Cut it.
To remove the chasis, press in on the tabs that are located on the chasis' side. Refer to the pictures to see the tabs. Once the tabs are being pressed in, pull the whole chasis out of the computer.
To remove the LEDs from the "chasis", push them from the front with a screw driver. To remove the button, you will need to push it from the back, the side with the wires. For clarification, see the pictures.
Not all computers may be set up like this, so your computer will probably be different. Just use common sense to find a way!