boykinip,
Most of the information came from the factory letter, some from conversation with Roy and David Carroll.
King did hammers, action work, and custom target grips, as well as the add-ons like the rib.
Somewhere around here I have a D.W. King catalog featuring all the handguns (Colt, S&W) as well as the long guns they sold.
It's from the late 1930's, and even includes the Registered Magnum.
A buyer could purchase a bone-stock gun from King, or the accessorized version...almost any way they wanted it.
Don

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