RPOO DPOO, you have supplied some excellent information there - I haven't seen it before. A couple of points/comments:
When preparing to assemble a tapered joint, begin by ensuring the parts fit together with a very high contact area. This means no burrs or dents on the parts (dents are always surrounded by raised up areas: that is where the displaced metal goes). When both parts are smooth and you think they fit, paint the male one with bearing blue (texta if that's all you can get), assemble gently and disassemble. Look at the blued area to assess the contact percentage, and find out where it does and doesn't fit. Damaged areas are repaired by localised fitting (scraping or filing). Poor overall fit may require lapping the parts together, or throwing one of them away.
Your information says the crankshaft uses half-inch British Standard Fine threads in both ends. This is a thread that has been obsolete since before the Second World War, and you have little or no chance of getting taps or dies for it, let alone bolts, except at a swap meet or flea market.
You have said ignition timing is one eighth inch BTDC. Do you mean measured by the piston position (1/8" below its highest position) or the flywheel position (1/8" rotationally before TDC)?
If someone can answer these questions, I think this post will be very useful in the Outdoorking archive.
