Here are the installed pictures, they should help guiding you for the installation.

I used a small flat head screw driver to pry the cover open. Be sure to leave the two holes open to let the cover to have something to grab onto (third picture). Peel of the backing of the sticky paper before finally install and don't pinch those two wires!

As for the back, I just pull the cover loose by hand, and install the LED. It's a little tight, but it's possible to get the LED installed.

Please be sure to test the LED before putting the cover back on, LED only works one way. If it doesn't work, remove it, turn it 180 degree and try again.
All of your LEDs were tested before shipping.

Thanks!