There's an interesting thread over in Pedal Steel on the history of a particular Emmons pushpull as it relates to Julian Waldman a/k/a Dave Burns a/k/a "Rojo", Johnny Rodreguiez, Lucky Oceans and the Wheel, the Bill Lawrence/George L. lawsuit, the Emmons family, and George Gruhn.
Sounds complicated but it hangs together. It's here:
http://steelguitarforum.com/Forum5/HTML/004586.html
Namedropping steel history
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