Pertronix module? You know how I feel about that. What you are describing sounds exactly like a bad module. You can prove it by throwing a timing light on and watching the spark scatter all over.
I’m not wild about the floats being a different height side to side inside the same carburetor, but I think your miss is ignition. Those floats have been exactly like they are for a long time- they were like that when the car was running well. Nobody got inside and bent them while you were sleeping.
95% of all carburetion problems are ignition.