Use the whole top end from a puch or figure out precisely what makes it work on a puch. Reverse engineering.
What it seems like to me is that crank case volume remains constant between the 4EZ motor and a stock chinagirl, unless he modified it differently (Stuffers nonwithstanding, my motor has those)
What we're trying to do here is make the intake of gases into the cases as highly asymmetrical as possible (Lots of fuel/air in, almost none back out) and utilize the area behind the piston not only for intake, but transfer. That means a windowed piston is required, and boost ports should be cut. Due to higher primary compression, transfers could be raised slightly, and re-aimed at the spark plug. Boosts could be aimed half the distance between the exhaust port ceiling and the cylinder deck.
I'm still reading as much as I can on 2 stroke porting, a couple more paychecks and I'll pick up a victim motor to play with.