I'd love a 70's 2 stroke to fettle in the garage, alas I've missed the boat, they're all either long since scrapped or way beyond my budget or sense of value. Many an hour spent in my youth stripping down, polishing ports, lapping heads, de-coking and finely tuning with claw hammer and a pair of stilsons. Adding an extra base gasket to raise the exhaust port was a hot tip. Another was to sand the head gasket to raise the compression. I'd estimate that all my efforts probably yielded somewhere between a 10% to a 90% loss in hp!
Stan Stephens is a legend, he had his shop within striking distance of a Saturday ride on my fizzy, alas, I never had the $$$ to ask for his help, so always rode at the back of the pack with a tool box strapped to the pillion. Happy days!