Steven, before you stick a bunch of money in your cast iron heads, you might want to check with Edelbrock and price the aluminum heads they offer. Quite easy to exceed the price of new aluminum heads with the price of the extensive mods you are considering. I did a 390 with the Edelbrock heads and Edelbrock Performer RPM package, (cam, lifters, intake, and carb) it ran very strong and that was toting around a '67 Galaxie !!! You can always wrap your stock heads up in a plastic bag and save them for someone who might want to buy your car with all the original parts.