When making assemblies, if we have a part that doesn't need a CAD representation, we won't put it in the assembly.  For example, rather than show plumbing or wiring routings in 3D, we have a separate 2D schematic.  On the other hand, we still need those tubes/wires in the BOM. 

It's easy enough for us to make written spec for such items using a Word document (for example) and then pasting that doc as a reference to the parent assembly.  This successfully lists the part in the BOM, and we can edit the quantity manually for each assembly.  So far, so good.

When we make an assembly drawing, it gets tricky because if we create a BOM table in the drawing, it doesn't account for those pasted references.  My default is to just write a note indicating certain items are not shown, but that's not as elegant as I'd like.

Does anyone know how to get those pasted references show up on the drawing BOM?