I decided on a carb rebuild and discovered the float bowl had a thick layer of sediment. Apparently I didn't get the tank as thoroughly cleaned as I thought.
Thanks to Maybellene for supplying a lost piece of linkage!!
Things seem to be much better - smoother idle, no leak, better acceleration, and the hot start problem seems to be solved but requires more testing.
My theory: the needle/seat contact was a mess leading to a bad idle, flooding after shutdown as gas drained out of the bowl, and a leak at the gasket as that draining gas hit the gasket and wicked out.
That's my story and I'm sticking to it...until experience proves me wrong.
