Replacing FAST EFI on HP 383, with what?

I have a '73 Space Duster with a 383 (.030 over) dropped in it. I am old school and hate the FAST efi. I am going back to carbs. Don't know how many cfm I really need and how many carbs to feed it. The 383 (400hp) has HP purple cam, roller rockers, Edelbrock alum heads, MSD, Edelbrock Al DP4B intake, 70 440 magnum exh. manifold w/ 2 1/2" exh pipes. Trans is HD727 with full go kit, TCI clutch and seals and Hughes performance converter and aux cooler. 355 rear end. I have read so many articles on the web and in both A and B Bodies forums that now I am totally confused and frustrated. This site focuses on 340s and 318 and a 360s. As expected. Please help me to decide on 3x2, 2x4, dp, straight 4?? 670cfm, 750, 850 1050?? Don't know cfm on 3x2, 2x4. I have a 850 4150 DP on my 440 (600hp) and know how it performs, but don't know how multi carbs would run on it either. Should probably stay with what I know, but need to explore the multi carb set ups. Any recommendations as to manifolds and carbs for the 383 would be greatly appreciated. Oh, one more thing. There is metal in the pan of the trans. Any recommendation on what level of 727 I need with this set up? I know this is not the thread for this, but I figure that anyone knowing what to put on the 383 in carbs, will know the answer to the level of 727 I would need. Than you