Pro Flo 4 Timing

If I understand you right that would mean the rotor and the post will fire when they are aligned at the middle, rather than when they are getting apart, ensuring a more direct spark path?. If this is so it sounds like a basic design issue Edelbrock should have got right since the beggining.

You got it spot on. It seems to be an issue specific to mopar small blocks, based on the replies on the Edelbrock forums. But, it seems to be fixed, so I'm happy to just move on and enjoy the car. Like the TPS I had to replace, not happy, but it's fixed now.