New to this stuff, about to pick up a very clean low mile 98 SS roller and I'm going to put a 5.3/4l80 into it but I'm curious about what harness to use. He has the 98 harness/ecu but they're not the best but I'm not sure on details why. Should I just get an aftermarket harness as I have a ecu from an 02 pickup with an lq4? Or try to find a stock 99+ harness?