When i first LS swapped the truck i did not have a V8 harness. So i just bought a Current Performance harness for my exact setup.Cage is getting there!
Did you extend the engine harness you already had or did you get another harness made?
When i swapped to the LSA, the injector plugs were the same because i was running L59 Flex fuel injectors and no extensions were needed. The only change was i needed a "breakout" harness to run the IAT sensor separate from the MAF. I have since just removed the MAF all together and removed it in the tune just running Speed Density on a 3 Bar tune. Everything else for the LSA was the same and just plugged right in as far as the harness is concerned.