Thanks to everyone for the instructions.  I couldn't push and turn the fixture by hand, but gently using a set of pliers did the trick.  So, it was quite easy in the end.

However, before looking too carefully, I tried to remove the light bult itself from the fixture.  After breaking the bulb, I realized that the bulb and fixture are an integral unit.  A piece of broken bulb somehow ended up in a piece of chicken that I was eating about 10 minutes later, so there's some kind of warning here.

I called the local VW dealer, and they can order the fixture/bulb unit for $1.65.  They don't keep the part in stock.  Just out of curiosity, is this a part that I might be able to find in stock at one of the national auto parts stores?  Unfortunately, unless I'm missing something, there are no VW specialty shops in New Orleans.

Thanks again,
David

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