sweet project, looks like those bearings fit into that crank housing pretty well.
The idea I have at the moment is for my 66cc kit bike. The bike is a mountain bike with the normal diamond back frame. My intent is not to completly dulpicate sbp's kit but to get the location of the jackshaft compaired to the motor. Sbp's location of the jackshaft is near perfect for my style of bike. Maybe I can just eyeball it.