Thanks very much for all of the input and interesting suggestions. Let me answer the questions posed:

Both meters are Luna-Pro meters. One on them had CdS written on the lower part of the face, and the other has no further information concerning the cell.

All readings were done in daylight, several different days, directly outside my front door in Florida. I moved from sunlight to shadows and took multiple readings with all meters.

The "white dome" was in the correct position each time.

Only incident readings were taken. I tend to use incident metering, and am very familiar with the foibles of using various metesr for incident readings.

Matt-I don't see any "transfer" scale on my meters. Perhaps I am missing something quite obvious? One simply reads the EV values, and moves the dial.

I am judging the meters purely on where the red pointer moves when the measurement are taken.