Hello, i have a 2000 mustang gt that just got 11 bolt PI head swapped. I went to turn it on and theft light started blinking. I called a locksmith but there was a voltage issue so he couldn’t do it, i figured out what it was plugged in my BAMA tuner since previous owner had mentioned bypassing PATS with it and tried both tunes but nothing. I called another locksmith again and he said PCM was showing a different VIN number and advised that a new ECU may be needed. Is there any ECU companies you guys recommend or how do i go about searching for a used one ?