Won't Start after Changing wires HELP

wires too taught would not cause the issue, unless the ends are not making proper contact. coil packs can not be out of order. I would look for a disconnected harness somewhere, like the harness for the coils

if the connectors are not getting down into the coil holes then you will not have spark. Well, you might have spark, it just will not travel thru your wires. Most the time you hear a significant click noise when you push the wires into the coil. You might melt a standard wire if you plug it into the plug wire. I do not suggest doing that. I would pull a spark plug out, plug it into a wire and set it against the engine block and crank it to check for spark.

I still think that for it not to start something has to be disconnected. Maybe a knock sensor. If you don't feel comfortable with the place it is at then by all means take it somewhere else. If it ran before you did the valve covers then I highly doubt that the ECM happened to go bad at the exact same time. I also don't think that all your coils went bad at the same time. did the coils have more than one bolt holding them down before you changed the covers? Are the covers painted? I am leaning toward your coils not being grounded well. You could always take 8 pieces of wire with alligator clips on the ends, clip them to the coils and then clip the other end to a good ground point. If it works then you found your issue.