I built the harness for my 1938 streetrod truck using a 360/408 magnum and a 1995 A-518, 4 barrel t-body, Stock ECM and injectors. It aint that hard, but it is time consuming. Factory electric service manual helps with pin outs. I started with a stock Mopar harness and a Ron Francis fuse panel and a few Ron Francis wiring packages. And a few beers.