318 Ignition

I've tried an MSD ready-to-run that failed right after I had it timed. I then tried two Pertronix Igniter II, both of which were DOA. I ran my engine successfully for over 20 years on an igniter I, but now I'm back to standard points and condenser. My engine is running, but not smoothly. Does anyone have a recommendation on what I should use for an ignition system on my Barracuda? Until I burned up a coil, the engine ran great on a Pertronix igniter I.