I ended up using one superlight (Mr. Gasket 925B) spring, and the OEM heavy spring with loop.
So it cranks at (estimated) 14 degrees for easy starting where the dist is currently set, idle is stable at 27 deg @ 1200 rpm, gradual advance to 35@4000, didn't want to rev the engine higher while leaning over it with a timing light. Still have the "13" (26 crank deg) slots which may be a bit too much advance at high rpm, although the inherent ignition box retard should keep it below 38. If not I can just back it off a degree or two until I replace it with an "11" (22 deg) piece.
The vacuum advance adjustment I still need to tweak, but it pulls in up to 16 deg at cruise (15" vac) which is also about right.
Now to start tuning the carb until I pitch it and buy a good one from Thumper