I've seen bare chassis sitting on dealers lots with such an assembly attached at the factory, and bungied or tied to the frame somehow so it can be driven prior to the dump body, or whatever thing is to be put on.
I can believe that in some cases this assembly is used as-is, and either manhandled into place, or adjusted to fit.
and in other cases, thor or sub-contractor, would add to or modify this thing in some way.
You can even see it in this picture, found online....
Thor Forums
