I agree with everyone .
That being said, when wrestling with the question "what is this meter reading, and how does it compare with what I am seeing?" I'm reassured by tests that use a visual reference.
I'm also reassured by sources that seem to indicate that the spectral sensitivity of meters is closer to the sensitivity of both films and human vision than what I had been led to believe.
I think I can now confidently move from Cds to SBC to selenium cell meters, with just minor modifications of technique at times where either UV or near infrared light may be more prevalent.
And I think I'll pass on limiting myself to a search for a Zone VI modified Pentax Spot Meter.