On the door switches which most of the lights are the doors,I had completely removed the small circuit board from the switch and found the - and + term that comes that gives it illlumination and put two leds in line (with the right polarity)and one resistor of the right size and solderd them in.I'll take a pick of my drivers door switch this week and post it up so that Itt'll help more.
List of must haves (at least I had to have)-
Gun type solden iron(pens are just to dang slow)
small needle nose pliers
Small screw driver for poping switches apart
small side cutter and end cuters(they look like catfish skinners)
Don't drink alot of coffee

Don't get in a hurry
Don't over heat the leds they cant take much
It cool to have a 12v battery on the work place or some way to test them out
Have to know wha size resistor to use in each aplication,1 led, 2led or four each take a differnt size.
Don't buy them from rat shack they are cheaper online (besthongkong or something like that)
3mm work good in small switches,5mm in some places like the shifter,fan speed.
If I get the time I'll try to do a write up or a walk through but it will probaly get buryed under everyone's elses threads
Hope I can help
