The Atom/Nova II modules will replace the points and condensers, but not the coil. Newer small engines such as Briggs and Strattons have the module built into the coil but most of these coil/modules are designed to go on the outside of the flywheel. The laminations are arced the wrong way. Finding one to fit the inside of a flywheel is the problem. A coil from a Briggs opposed twin might be able to be adapted to an outboard coils lams but I don’t know. Size and magnet polarity might be a factor in making it work though.
Studying photos of small engine magnetos on Ebay might yield some results. I know there’s lots of cheap ones there from across the pond and they are meant for small engines powering scooters and mini bikes etc.
