Quick answer... You need a circular knee lever like
https://www.vintagesingerparts.com/p...=8009364471838 There were two styles of knee levers, one round and one flat. ETA- I think there is a third kind for a knee bar/lever that works for a "portable" that fits in a cabinet.
The circular plugs I believe should screw apart to be rewired.
Janey - Neat people never make the exciting discoveries I do.
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