I had some free time today so I decided to investigate for myself the factory yellowish LED map lights. I know a few guys have already done the mod, but we were lacking some good photos of what's all involved. I did not change the LEDs yet as I wanted to see if it's something I wanted to tackle. Overall they are easy to get to and simple to take apart the boards and get to the actual LEDs. As mentioned earlier in this thread the toughest part will be the soldering.
It looks like you'll have to remove the ribbons going to each LED board. I see two solder joints which should be relatively easy to do, they are pictured below underneath the black tape. You will then attach the new LED either ontop of the old LED or right next to it, or come up with a custom mount that doesn't use the existing board at all. Then solder the two wires to the ribbon that you removed before.
This is assuming you have a pre-wired LED and one with adhesive backing. If I do this mod these are what I will be purchasing which are pre-wires and have adhesive backing:
Put everything back together and you're done. Based on what I saw and my experience you should be able to do this mod without permanently disabling or damaging anything factory. In other words, if you want to go back to stock someday you should be able to without too much issue.
Hopefully these detailed pictures help some people out.
Top of console after screw removal. 12 T10 torx screw.
After removing top panel. Circuit board is now exposed.
Removal of circuit board with all the buttons.
Separation of circuit board.
Removal of LED map light circuit board.
Back side of LED circuit board with tape peeled up. Here you see the two solder joints that need to be un-done. After those are remove the new LED wires will solder back to that ribbon.
Next two pictures show the panel re-attached and turned on. You can see the color difference between the factory LED map light and my aftermarket "natural white" bulbs from superbrightleds.