My coil went and had the same sympthons as described, misfiring etc. I knew it was the coil, so safe in that knowledge I went off to the motor factors to collect one. Installed in 5 minutes and was smooth as silk running.
The next day misfiring again, checked everything over, lead, plugs, oils etc. No joy booked into garage and the spurious coil was at fault casue not generating enough volts. When buying the new coil buy from fords.