For the magnet install...machine a ring that slips on the flywheel or hub. Install magnet in ring and a small setscrew on the opisite side of the ring. To get the right timing...just loosen set screw...and turn ring a tad.

The carb may be tricky.But a regular glow carb may work if it will draw fuel & if the needle is not to touchy to adjust. Look up a small RC car that was made in Italy. It was about the same cc & was gas with CD ignition. Capt,n

http://www.classic.rc-junkies.net/?page_id=637