We installed the COP package on my 3KGT Gen2 with AEM EMS2 yesterday. It is a lot of work, but if you follow the ínstructions closely and have a helping hand, you will be rewarded by a cleaner engine bay and less trouble with ignition coils and PTU failing.
We managed the installation in one day, could have been quicker, but I mangled the ECU connection, and it took some time to get this cleaned up.
In one sentence: Not easy, but rewarding.