OK, so let's say I DO have access to the whole car, what then? Can a 2004 ECU be used? Will the 2004 ECU work with the 2005 wiring harness?
Don't take this the wrong way. I'm not trying to make more work for myself. In fact, I'm actually trying to talk myself out of using the 2005 w/immobilizer.
I'm trying to learn as much as possible about this stuff. Somebody asked me yesterday "Why can't you just use all of the components that make the immobilizer work?". I didn't have an answer other than "I'm not sure".
That's why I'm asking these questions. Thank you for being patient with me while I'm trying to learn about all of this.