How do you catch the right timing when replacing the timing chain on 2000 mpv engine?

I had a great experience changing the timing chains on a 2.5 liter V6 and let me tel;l you it's very tricky and not even the dealer book was right. Took it to diffrent shops and they couln't do it. so I finally done myself and I nail it right on the money. Is hard to explain but if you really need somebody to help let me know or send me an e-mail at jrodtitan@gmail.com