Tools,soldering iron- 30 watt is is prefered, a t8 security screw driver to remove the screws, and solder, and small tweezers to grab the LEDs, also 0603 LEDs are what you will need to use

Step 1, after you have removed the case you will need to get a small solder ball and put it on the led, this will remove the led if done right. Once you have taken the led off and have the excess solder removed you will want to get an led out
Step 2, I like to have a power source hooked up so that I can tell when the led is in the right spot
Step 3, now that the led is in the proper spot you will get a little solder on your soldering iron, now you may want to hold the led down with a pair of tweezers
Step 4, solder both side insuring that the led is firmly on and won't come off easily.