i have a 69 r/t with a very similar engine build (kb184 pistons, stock intake and carb, stock exhaust, mopar 272/.455 cam) to what your putting together. I would use the summit 6401 or the crower 271 cams and forget about the rest. if headers are what you want then buy the smallest tube. I would consider cast manifolds but small headers are o.k. a good fuel pump like the carter 6903 is a must. my car has power brakes and believe it or not I've had a difficult time getting enough vacuum to operate them with near stock cams; so avoid the cute idle thing. pocket porting is worth while and I like the ferrea 2.08/1.74 valves in those stock heads.