I have looked your motor up in an old Peterson's spec book I have, and the stock timing spec is 10 degrees BTDC at idle speed of 800 rpm on a standard transmission and 600 rpm on an automatic transmission.
This will give you a starting point but I will be willing to bet your timing spec will change with that Lunati cam you have in there. I would contact Lunati for that. They may have a web site you could get that information from.
Another method I have used with great success on 4 cars of my own is to set the timeing using a vacuum gauge. If you are interested in that let me know and I will post it up here for you.