I have the same engine and the same haynes manuel.
it has two diagrams in haynes on the same page. One is for earlier 3.5 engines and the other is for 3.9's it says which ones which!
The diagram shows you which is which on the dizzy and which plug it goes to, I did it last year its not that hard, I turned the book so it was the same way round as the real engine and went from there.
btw stu is playing catch up form his holiday at the mo, he rang me today. give him a call monday mate.