Title says it, there has to be a simple way to take two objects that are intersecting, create vertices at the intersecting ponts, delete the faces leftover on the inside, and combine the objects into one hollow mesh for sculpting. The reason I need to figure this out is that on my first sculpture I just joined three meshes, sphere for the head, cylinder for the neck, and rectangular prism for the body, then went ahead to sculpt and the meshes just over lapped. As you can see here in the neck.
My goal is to get one wire mesh from three shapes, not three shapes that are joined, but overlapping.
Here you can see my problem
outside
inside the cube
inside the sphere