hey I’m looking for some direction on trouble shooting. I have A 2004 GTO front mount s475 custom tune car ran fine until I cracked the piston, shoved a 2003 5.3 block in it, moved all sensors from the ls1 to the 5.3. I have Spark and plenty of fuel at the rails. Fuses are all fine. Also when I have the car in the “on” position there is no power at the injectors. Please help.. I’ve been searching various things for the past week and trying everything. All the wires trace fine and have continuity from the PCM to connectors.