awesome:  Yes, I knew Mason Williams played nylon strings, but on the Howe piece, those really didn't have that sound that gut strings have.  After listening a second time, I can catch phrases where they sound nylon, but during most of the performance, they sound like steel.  The difference must be in the guitar.  Thanks for that information.  I'll be more on the lookout for that.  I thought my ear would hear the difference.  Evidently, not always.