Hey Mike
My HM80 flywheel will not fit on my HM100. So if you have the older HM80 with points it wont fit eather. The Hm100 crank is bigger. The head, intake, carb, breather, and flywheel cover are the only things that swap. At least on mine. The HM80 is older, and my HM100 is the newer style. Im working on my Star clone right now. Ill let you know how that turns out.
Josh