Doing an air leak test on her, she's holding on at 6psi. It was hard to seal the spark plug, I ended up removing the washer and using an o-ring. I used a stethoscope with the bare tube end to probe inside of the stator and gearbox, all is quiet in there.
Still have some rust spots inside of the tank
but for the most part the vinegar has removed the rust to bare metal.