right now the belcrank I have is difficult to get a picture of. heck I can hardly get my hand on the thing, giuliettas don't pack extra room.
It mounts to the two extra holes on the weber intake manifold, below the second (from front) carb. The mounting section is a stamped piece of steel that narrows to a axel shaft on which rotates a belcrank (looks like hands of a clock set at eight o'clock).
Each hand has a ball link on its finger ends. One end attaches to the throttle by way of a shaft and the other attaches to the butterflies through another ball link on the webers.
750, 101 (veloces) and some 105 cars (carbed) used a belcrank.
kinda afraid this discription is jumbled enough that unless you have one in your hands you won't "see" it.