The CDI kit shown here can be used on ZA50 and E50 Puch motors. Most of the time they can be bolted in directly without modification. However when switching the CDI unit between the E50 and ZA50 the ignition coil must be unscrewed and flipped over then re-installed. This is due to the rotational direction of the engines being opposite, thus the electrons in the coil will be moved in the wrong direction by the magnetic field of the stator, failure to do this will result in a weak spark at the spark plug.
For the E50 it is installed as shown below. You will have to remove the brown ground wire from the back and put it on the front. At the same time you should swap the screws on that coil, as the longer bolt interferes with the case if left on the left side.
Some kits required enlarging the adjustment slots in the plate in order to get full advance. Others have bolted with no issue. If you find that your timing is retarded still with the plate at full advance, you likely need to break out the dremel. Moving the pickup to the other side causes it to be advanced too far.
The 12v CDI Ducati exciter coil on the stator plate (white wrapped) from a Puch Korado, will also work on this CDI kit.
The white wrapped with red lead coil is the (high tension coil) or the high voltage coil for the spark. The other coil with the yellow lead is the light coil or low voltage, it puts out a range of around 12volts up to and over 20 volts @ high revs. That's why you should run a voltage regulator so you don't blow your 12volt bulbs.
For the ZA50 the plate is installed as below. It should bolt right on, no reported need for modifications.