Old school simple basic and easy. Pop a spark plug on no 1 cyl lead and earth it with a jumper lead. Set engine on no1 TDC firing (Yip no6 rockin) align timing marks on ya 10 degree or so. Ignition on dissy loose rotate dissy in advancing direction until no sparkin plug fires and lock it there. When you fire it up and then use your timing light you will see the old school basic common sense base timing setting system as described IS as ACCURATE-as ya timing light...lol