Stefan is correct. I had this exact same problem in a 404 (Arnolt) when I first purchased it (used). Somebody had bypassed the resistor. This will also burn up the points. My 40 year old memory says you want about 9 volts to the primary side of the coil.
I don't know the configuration in a 407, but here's a picture showing a typical resistor (lower left) and coil.
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