<VV> Instrument panel lights stopped working on a 65

[Edelstein and Payne]

Folks,
     One night last week when my son was driving home from his job late at night, he "smelled smoke" and the instrument panel lights went out on the 65 coupe he drives.  The "smoke" has not happened again, but he has no dash lights.
     This weekend I spent some time under the dash, and could not find anything that looked like it had shorted out --- nothing looked "burnt".  All of the fuses are good, including the one for the panel lights.  My first thought is possibly the headlight switch, as the brightness of the panel lights is controlled there (note:  the headlights are working fine).  What are the other likely casues???

             thanks
                Travis Payne     65 Monza coupe
                Raleigh, NC      65 500 coupe