Supposing a fella had a 2011 Corvette, LS3/M6. And that fella acquired an LS7, or at least its equivalent (sleeved LS3 with LS7 pistons/cam/heads/intake/et al). Am I correct in assuming that all one would need to do from an ECM perspective to make it work is flash with a stock LS7 file?

Part two - further suppose that said fella had a 2010 Cad CTS sedan, DI 3.6/M6. The LS3 from the Corvette is an easy swap mechanically...but what about the ECM? Presuming again, is it as simple as swapping the SIDI controller for an LS3 controller? I don't know if the connectors and/or pinouts on the harnesses are compatible, but connectors can be changed. Since manual trans, no AT controller issues...CTS tach will want a different signal frequency...any other things I'm missing?

Thanks in advance!