Well it sounds like I'm too late in that you've already ordered the plug and play harness. I couldn't justify spending the $80 to prevent cutting ONE wire. If I remember correctly, it's the white wire (EST wire) in the ignition module harness...the white wire closest to the fire wall. I admit it's tough to get in there to cut the wire and properly and securely splice in the T+ wires, but definately worth not spending $80. Anyway, your choice. Good luck. The T+ with the LT1 MAF is a good setup...so is the Extender chip if you got that too.