If that is the code your getting and you replaced the #5 coil the problem is either the wiring or the pcm. You can swap a coil with another cylinder just to make sure you did not get a defective coil and the next step is to check for shorts, connector conditions, or high resistance in the wiring. Here is a wire diagram, let me know if you have questions. Thanks
P0355 Ignition COP 5 Primary/Secondary Circuit Malfunction - With Automatic Transmission
wouldn't the igniton start/run switch affect the power supply to all the coils in lieu of just one?
I replaced the cop with a new one two times with the same result and the connector appears clean and straight prongs
would the pcm affect just one coil and I assume a new pcm would require to have the parameters installed by Lincoln