The ONLY issues that I have had that are similar were related to the MSD system and system failures.
Those would also give symptoms of a failing coil but it was the brain itself that failed. In my case three times over a period of about a year. Perhaps the "brain" in your distributor, Petronix calls it the "ignitor", has failed? In the beginning people were carrying spares since failure was so common.
In my Pantera, I went to the Ford Motorcraft pointless distributor and system. It's been in there at least 20 years with NO issues.
George likes to recommend the Duraspark I. He was familiar with it since it had such a high, common use in California for emissions reasons. I am using the Duraspark II which I suppose that you could say is like the 49 state system.
He likes to point out that during cold cranking it retards the advance to make it easier to crank the engine. I have no argument about that and it is a good idea but have no experience personally with the Duraspark I.
I WOULD HIGHLY RECOMMEND THE MOTORCRAFT DURASPARK II SYSTEM.
I don't really want to complicate this response but in my case I replaced the Ford Motorsport "brain" with the Pantera-Electronics Ignition Controller. The reason is a little more complicated but here are a couple of reasons.1) the P-E Ignition will actually fire a fouled plug and clean it up. Webers under certain circumstances CAN FOUL the plugs. I'm running Webers too. NO OTHER IGNITION SYSTEM WILL. NONE. 2) with the Ford Motorcraft you have to finagle the Pantera tach hook up. With the P-E, you just plug it in. 3) there are addition features (research them on the P-E site) that are very inviting.
The BIG advantage to using the Ford system is that if it failed on the road, you can get parts for it at virtually any auto parts store and use any replacement brand.
Because of so much bad history with the failed distributor drive pin, that is something that you just need to verify by pulling the distributor and examining it BUT the common denominator there was a FORD DISTRIBUTOR that had been rebuilt by someone/some shop previously and obviously used the wrong strength pin.
Remember that in any replacement system that needs to be run by a 12v supply from the ignition switch, The original Pantera system is a Ford system and uses a pink resistor wire which reduces that voltage to 6v.
Some say that the replacement systems will run on the 6v for a while but will eventually fail. I can't confirm that.