You would use a relay with a resister to activate the starter circuit on an automatic transmission car. I suppose you might be able to use a relay on the CPP if you can get a reading on what the CPP is sending to the ECU. I'm skeptical of it simply being a 180ohm resister because the resistance must be learned by the ecu (or maybe bcm) before the car is allowed to start.
If you are going the resister and relay route, you will need to do both the ignition and the CPP with separate relays.