Reassembling the drive cone is pretty easy considering that there are only 4 pieces to it.
Now if you are figuring out how to adjust the spring I would say that the easiest way to do it is to place cup down onto shaft. Insert spring. Place cone on top and wind clockwise until it catches the spring.
Lightly lift the cone upwards till you feel it goes over the notch on the cup and make sure that the spring goes with it.
You should now feel a bit of tension from the spring when you that would travel counter clockwise.
Tighten down screw and you should be done.
I play paintball.