Disconnect mag power wire. You do not want battery power to go thru the mag, otherwise you may burn out the coil. Either buy a low rension coil, or in a pinch, you can use an auto coil from a GM car built in the 1960s. Wire as follows: 12 Volt battery + post to a Knife switch (so you can kill the ignition). Switch to the igniter power post (Fahnstock clip on igniter). Engine block back to battery - post. NO condenser is used - you need the flash at points break to ignite the charge!
As this engine is a throttle governed engine, there is no battery saver. As the trip rod winds up the igniter, the points within the cylinder are closed. When the igniter latches off, it rapidly opens the points, creating a flash which ignites the fuel/air mix in the combustion chamber. DO NOT over oil the igniter - too much oil will foul the points and make for a bad internal grounding. To run on the mag, the magnets on the mag must be strong. The hatch marks on the mag armature must align exactly with the mark on the mag case, when the igniter latches off. When the engine is running, take the power wire from the mag and try wiping it against a clean bare metal spot on the engine (NOT THE IGNITOR!). If you only get a weak flash, you may have to get the magneto magnets charged. A strong bright flash may mean that timing is off between the mag and igniter. No flash may mean bad coil or stuck brushes, or worn bushings. If you don't have experiance taking the mag apart, take it to a good mag guy, as if you do not do it right, you could damage the armature. The mag guy can charge the magnets while he looks the mag over. DO NOT rmove the magnets off the mag!