How to convert Puch VZ50 to 12V DC electrics?

My Puch VZ50 (the yellow one, but with engine from the black version) churns out 6V AC, hopelessly feeble. If I could convert to 12V DC generator the options for lights would be endless - including LEDs, and fitting winkers. Is there a conversion kit? Would a later model engine have a 12V generator in it?

Tim
October 2012