KZ1000 engine help

Hi all. I am new here. I was given what I think is a 1979 KZ1000 engine. I am having a hard time finding the engine numbers so I can track down the year. It is going into a "GOkart" I did not want to go too far with the build till I can get a wiring diagram and get it running.
I have enclosed a picture of my last project and now want to go all out with something new. Thanks for your help in advance.