How are you greasing your COP's exactly?

 

Also which misfire DTC's are you getting ? That will help.

 

spark plug end and electrical connector ends with dielectric (is that the right word?) grease.

 

It's right word, -,clean the grease from spring tips. How you do that, reach in the boot a screw driver or hemo's, pull the spring past the boot end about 1/4-1/2". Hit the spring with a good degreaser (Lacquer thinner). Let the spring go and recoil back into the boot.
Clean the harness connectors well (are those the connectors your referring too?), use compressed air and electrical cleaner.
Most dielectric grease is non conductive, COP boot springs aren't strong enough to cut thru it for a good connection. Not like spark plug wires are anyway. For the connector/conductor you use a different type grease, I believe it's called OX-Gard. It's a dielectric the improves conductivity, - made for connectors.

Which are you using btw ?

 

Are you getting PO304-08 or 35I-358, - any 316's 300 ?