Engine numbers

Hi, all. I,m new on here and do have a question. I was given what I think is a 1979 kz1000 engine. Where would the engine numbers be, having a hard time finding them. I am building a "gokart" around the engine and do not want to go too far till I can find the year and get a electrical diagram.
Thanks all, I will keep you posted on the project if I can ever get this engine to run. I have enclosed a pic of my last project.