Misfire - Ignition Advice
Old Mopar Distributor
Bushings
Distributor cap/rotor
Rotor Phasing
Did you check the gap on your reluctor / pickup coil ? .008 with a brass feeler gauge
Check it at all eight points on the reluctor , see if the pickup coil is hitting the reluctor while spinning
Could bee the pickup coil itself failing also when hot
If you think it’s the MSD Streetfire Ignition Module failing , how hard would it be to reinstall the Mopar/Chrysler ECU or Ignition Module on the firewall , or even a points distributor