Replace the crank. You can then use the cheap LePartie CDI with a woodruff key and stop fucking with timing settings. The Airsal is cheaper casting than the Parmakit. With a little prep work they are close to the same.
15mm or 16mm will be fine. The stock head is fine with a gasket or polished up to run without a gasket, the stock pipe will blast but no power gain like a chamber pipe. The stock crank is like a 3musketeers candy bar. Soft as fuck on the inside.