need some help with tradeskill idea

[Dehumanity]

Hiya,
Im trying to take the Jonas hand quest and turn it into a tradeskill combine.
im trying to use the pieces of each as sub combines then add a couple dropped items for the actual combine
( ex. combines to make distal phalanx, metacarpal, mid phalanx, and proximal phalanx plus x item to make each finger).

Now what i have no idea about ( this being my first attempt to make a tradeskill recipe) can i use the same recipes to make the separate pieces and still use them plus X item to make a finger. Or am i better off doing them like they are in the actual quest naming them separately and adding a drop item to make the fingers?

in the end i want to players to use these as a skill raising combine then take the items plus the unique items to make the augs. they can take the fingers plus the backhand and either use them as armor augs or be combined to make something else.

Any help would be appriciated, i have a very general idea on how to set the recipe up from reading im just looking for the most direct way of laying this out.