To process your inquiry we need to know what type of ignition/generator you originally have If you click-on the type designation you will find more information and questions we would have.

identifiable by a magnetic drum, that turns outside around the coils

identifiable by the existance of carbons

identifiable as it is a separate device mounted externally at (or on) the engine

flywheel magneto
(internal rotor)

Occasionally the ignition parts are mounted at other places (e.g. cylinder head).

There might be 2 devices - one for ignition and the other for power generation.

identifiable at a magnetic drum, that turns inside the coils

 
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