3 Truck Climax Parts

[bbellm]

Finally got my hands on a Climax.  3 Truck.  Bought off of Ebay, might have been a mistake.
It is missing the entire 3rd Truck assembly.  I have looked for one on line, but all I can find are the diagrams for the "Exploded" truck with all of the parts that go into it.

Does anybody know what the part number of the entire assembly would be, or know where I might be able to find one, or am I better off just trying to convert it to a 2 truck?