This project has been going on for a while, so I skip ahead a little bit and publish material from the current progress. If or hopefully when I get it to work as desired I will probably post a full description of the whole project.
Recently I've mounted a hallswitch underneath the flywheel who's task will be to trigger another circuit I've designed. That circuit in its turn will do more or less the same thing as the mechanical contact-breakers on the original system (main difference that this system will hopefully work).
The hall switch is a switch that is activated by a magnetic field, and has in this case more or less the same task as the ridge on the flywheel on the original mechanical ignition system.
The hall switch is inside the green heat shrink tube mounted with stripes, connected with a lamp cable that proved to be practical and sturdy. The sensor output is surprisingly precise and clean.