CH did make a shielded plug cap for the 3/4 hex plugs and was called a Botch cap I believe.

DA/3W/ZDZ ignitions are completely different ignitions systems than the CH style ignitions, They are timed from 3-6 mm before top dead center and to use a CH style ignition with new sensor and sensor bracket you had to drill and tap new threads in the engine to time it right.

About two years ago we deigned and manufacture a system that will allow you to use our ignition without having drill and tap new holes, It is a direct bolt on using existing mounting holes on DA/ZDZ/3W engines.

Milton