Better Performance Output

Im doing something similar with my 73 340 dart. Just a bone stock engine right now. Im adding air gap intake, AVS2 650 carb and tti 2.5 exhaust. In my case I dont think anything more than a 650 carb would help. Im staying with the stock exhaust manifolds so thats going to be a bottleneck.
I think your build could handle a 750. You didnt say what cam your running, is it stock?