That's even easier. Remove all keycaps, you will see the screws. Unscrew them. Disassembly done.
To find the correct holes, if you look on the switches, there is this a cutout where a LED can fit in. Here's a picture, red are the connectors for the switch itself which you should not desolder, blue are the connector holes for the LED. Switch picture stolen from Thechemist, markings by me.
Edit: found a good picture by WhiteFireDragon, heres a good view from the PCB, again do not desolder red, desolder the blue holes.