Tacking down the RGB LED

The white plastic case melts very easily, almost instantly. The PCB on the other hand can withstand a lot of abuse using a 350°C (662°F) iron. Therefore it's OK to place the iron's tip directly onto the board and slide towards the pads. Always try to touch the pads on the PCB first.

Flux it up!

Use Sn60Pb40 solder and 240°C and they will survive.