Following outlines how I changed the little light bulbs inside of the seat heater switches in my 04 Altima to LED bulbs...

-First remove the rubber gasket that surrounds the shift indicator bezel from the finisher piece on the console(silver piece pictured). Simply pull it up and out.

-Remove the finisher piece around the shifter. Place towel or something to protect shifter bezel, and use screwdriver to pop panel loose.

-Remove phillips screw inside box in bottom of cup holder

-Pull E-brake up, and open console storage compartment.
-Pull up on cup holder assembly from where the other console piece was removed.
-Guide assembly over E-brake

-Remove plugs attached to seat heater switches
-Remove switches from panel

-Switch removed
-Begin disassembling switch by removing the rocker portion. Use a small screwdriver to pop the sides over the little retaining pins
-Finish disassembling switch by popping the guts out from the bottom. There are 2 tabs that have to be released, and they are a PITA. I slide a jewelry screwdriver under each one at the same time.

-Pic of the guts of the switch.
-The yellow/green piece on the left side is the LED that lights orange. This piece slides off of the contacts
-Normally there would be a similar holder to the LED for the bulb that backlights the whole switch white...I replaced mine awhile ago with a modified LED bulb that needs to be replaced again.
-I used a #74 white LED bulb that I cut apart. This gave me the LED and the resistor needed.
-I installed the switch to check polarity on the LED, and then soldered the legs to the contacts of the switch.
-Pay attention to the way that the white plastic piece that moves inside is oriented...

-Pic of white plastic piece and the contact piece removed

-How the contact piece is assembled. The forked copper piece kind of clips into the white plastic holder with the rounded edges of the forks facing you.

-Switches reinstalled, with bright white backlighting
-Reassembly of vehicle is reverse of taking apart.