This will be my first tbi conversion: 69 camaro, 700r4, 3.70, 355ci, 9.5cr, 193 heads, melling mtc-1 cam. I have tbi harness and parts from '88 gmc van(7747 ecm) with 350. I have also picked up a 16168626 ecm and a 16197427 ecm. Since this is my first conversion should I use the 7747 and change to one of the others later? Or should I jump in with one of them from the start? (I understand I have to change the pinout) If so which one should I use. Thanks in advance for any help.