I've actually run into a similar problem. I just tore my dash apart to get the Becker radio out, and ever since I pulled the radio out, the upper center console stuff (rear light, antenna, etc) doesn't light up. However, like you, the Defrost light lights up. Also, all of the ACC push button lights that worked before work now (I'm pretty sure I have a dead bulb, though, so I wanna replace that; I pulled the ACC part apart as well, so the push buttons are just sitting there right now). There is what appears to be a light bulb socket behind the ACC buttons; it has the same series of wires that run to the ACC light bulbs, but doesn't appear to be lit...even though it's facing backwards, I wonder if it could be fiber-optic'ed up to the switches above the ACC stuff?
So I'd like to know as well.
Also, where can we find replacements for the light bulbs? And what's the best way to go about pulling the bulb sockets out of their holders (i.e. in the ACC) without breaking the ears? Someone did that with the light that lights up the temp wheel on mine, unfortunately...I don't want to make that mistake myself...