I have replaced the lamps in my radio on the S70 and posted my notes a few weeks ago. There was another post on this for the 850 in the archives. He had a different radio that I did so there are some differences in his post and mine. I also have some pictures that I took on the process but I haven't figured out how to post them here. In short, it's about 2 hours to replace all the radio interior lights and you can get the bulbs at your local radio shack. I would suggest that you do the same and replace them all since they all have about the same life span. The bulbs are very small and you may need a magnifying glass to insert them in the bulb housing. Post or send me your email address and I will send the pictures.