I think I would check the Pertronix. Fixing for the module might have come loose, gap will change or it can be bumped by the magnet ring. Or, the magnet ring might have got dislodged. I had to do a little filing to get mine to sit down correctly but I've read that others have had to use a bit of tape to keep them from moving.
If you've got carbon leads, a nice new bit of copper core for the coil to dizzy lead might improve your spark.
DON'T leave your ignition on with your engine not running or you'll fry your Pertronix. I don't know what the safety margin is. I do know it's instant death if you connect it up to the coil the wrong way round. Yes I did.........