With Morph Manager 4, If you use the trick of loading a pose first, you will be able to see all the channels in the BODY actor and delete any of them.

Morph Manager 4, isn't really a good way to do that part though, as it's hard to tell what is or is not a valueParm channel. Better to use a Poser file editor like the free "CR2Builder", or "CR2 Editor", or one of the commercial ones like the ones by Dimension 3D, or PhilC.