Internal threads on Victrola Crank

[Gleemanguy]

I am wanting to cut down a Victrola 10 tabletop crank to fit a Victrola tabletop 12. The machine shop is not sure of the thread size. They asked me if I knew if it was a ¼ inch - 20 pitch thread. The machinist didn't think the 20 pitch was correct and wanted to verify the correct size??? Does anyone know for sure the correct size and pitch. The crank has female threads. Thanks..Jack