Thanks for the input guys....I've gotten alot of advice from alot of guys. I've been doing some looking around...
I went to the buyers guide for mopar crate engines, it states that for THESE engines, Mopar recommends a 750 Holley, but the only thing the crate engines has in common with mine is the Magnum heads.
I went to holley.com and ran through their interactive carb selector, and the Street Avenger carb that came up was the 770 w/ vacuum secd's.
I went back to the one book I bought, "How to Hot Rod Small Block Mopar engines", Chapter 13, pg 178, under carb selection, it states for a 360 for performance/racing applications to use a 750 CFM.
When I go through the equation: CFM= (RPM x CID)/3456, I get 6500 x 365/ 3456 I get 686.4873.
so it seems I can go either way, go 670 and fattening it, or 770 and leaning it back. Am I right? If so which wouldbe better?