(I've forgotten how to do this) I have a part. I've brought it into an assembly. In the assembly I've done some extrude cuts to the part. I want to save out the parts that have been modified by the cut made in the assembly. I believe I turn it into a multi-body and save the two separate bodies. I do not even see the bodies folder in the assembly tree. I forget how to do that.
UPDATE: I've attached a sample assembly and the one part within the assembly.
\krauster
Do a "save as", and save your assembly as a part.