Hey Ed,
I'm working on the same project but I deal with a 318LA block from 84 that will go in my 77 Fury. By now I figured I will go with a the 4" stroke crank and machine the block .030 over to make it a 390. Right now Im debating with myself if I buy me a set of Aluminum heads or just let the cast Iron ones I have machine for the bigger valves (2.02" and 1.60"). I saw a set of cast Iron Indy heads at summit wit a 1.94" intake that was very inexpensive. Well will see about that. If you plan for 600 horse make sure you get a forged crank and a set of good quality rods. Im sure the book told you all that already and much more
Tomi