by the way, if you buy those particular injectors from that particular seller...I suggest immediately sending them off to be charted. That particular seller is the one that was involved in some controversy over the supposed "flow matching" they do (or dont do). Also dont expect to recieve the flow sheet they say they will send. no one I know who ordered from them got one.
I didnt flow mine...and the guy who bought it recently melted a piston...coinicidence? I dont know.
as for 4,5 and 6 you dont NEED them but they are nice to have for more control and tunability. They can be added later. In my opinion they make an otherwise simple mod more complicated than it needs to be. If you go with the last 3 be prepared to do more tuning.