Currently car has a FiTech 1200 and MSD 6014 box. It's a Gen 3 6.0 bored .60 over with 24X tooth reluctor. 4L80 setup with MSD controller. I would like to change over to harness and injector setup with GM ECU. My question is which ECU should I get? I want to be able convert over to SD 3 bar or at least 2.5 setup. Thanks in advance.