I need advice about the right Holley Carb

Do you have dual exhaust? Headers? Engine stock?? Any Holley from 600-750 for your liking. 750 3310 is a good one, and so is a 670 Street Avenger. Look at Quick Fuel Brawlers also.....
I have a dual exhaust. Just put in. No headers. I was thinking Holley 650, 4160? Newbie.