Engine wiring help

Well heres a long story short. The guy who put the carbed 5.0 in my car did such a hack job its a miracle that the car runs and everything functions as it should. The car had a 4 banger in it and he just hacked up the harness to make it work with the 5.0. My question is, is there any harnesses I can get which will cure my wiring nightmare or do I have to rewire the whole thing piece by piece. Also what uneeded wires can I take out and still have the car run as It should. Thanks and sorry for such a noob question. :rolleyes: