is there any difference between au1 au2 and au3 engine wiring looms for 6cyl engine? amd what are they?

I don't think so...

I fitted AUII wiring looms to my ED... To test everything first I plugged the looms altogether (engine bay to body to dash) with all the modules and just plugged it into the motor already in my brothers AUI one tonner (my AUII engine bay loom into his AUI engine loom)... Bridged his fuel pump relay and hit the key on my AUII looms and it started his ute no worries...

On a side note, if you think about it that's concerning... You could have a security removed PCM, with a a very simple loom... Break into a car, pop the hood, disconnect the engine loom plug and plug it into your own... Hook power to your simple loom and hit the key and off it goes... Very simple to steel one...

Cheers,
Tim

thanks didn't quiet understand the part where u mention bridge the fuel pump relays?