IS 700 HP POSSIBLE WITH......

Even built as a 505, I think one that made a true 700hp would end up being rowdier than what many people envision them as being like.
True. It will be loud and needs to be kept in excellent tune or else it becomes a real pain to keep running. EFI can help, but then the person needs to understand enough about EFI to keep it running.
600 hp is a better target for a street driven BB Mopar.