To be clear, I'm talking about the soft button controls: To get at the bulbs the cover (the buttons) have to be carefully pried off the switch housing. As I said, beware, if your buttons are old they may crumble. If I recall correctly, the white plastic circuit board came out with the cover. When I did mine, the board's plastic retaining clips in the housing broke. This was not a big deal as I had a spare housing, but if I'd known the board would come with the buttons, I probably could have prevented the damage. I think you can get replacement bulbs from RadioShack, but they wont be green. If you're really lucky, you can sometimes remove the tiny green cover from the old bulb and transfer it to the new bulb, but don't could on it. Another good source for auto bulbs is
www.autolumination.com but the shipping may be more than the bulbs.