The points pin where the spring sits on is short and shouldn't be tall enough to touch the cover. The points spring needs to be in contact with the pin as that's the transfer of the connection to the pin and the condenser. Make sure that connection is clean. Clean the post and the spring.
A cause of running erratic is typically the case seals. Leaking seals will affect the vacuum/pressure pulse pressure of the carb diaphragm and that's how the diaphragm moves to pump fuel. When fuel is pumped erratically it will run erratically and no adjustment to the carb is going to fix that.
Clean ALL the points connections
Add a few drops of DOT3 brake fluid (Not synthetic ) to each of the crankshaft seals with them still in place on the engine. Let it sit at least over night. Brake fluid swells the rubber and most times will be enough to seal the crank. There are other little O ring seals at the points push rod and the one screw for the carb. If they are missing it will cause a big leak
Bent or damaged carb to case gaskets can do the same thing