Moving bones without moving mesh

Hi All, I have a rig imported from Maya which has a few Meshes in it which are driven by bones.

During game play I want to be able to modify the mesh, and then move the bones so they align with the new mesh. For example, if I have a bone which is positioned flush with the mesh, and then the mesh becomes wider, I want to move the bone so it is still flush with the mesh.

I have tried to move all the bones, and then apply the mesh vertex positions, but this doesn't seem to be working.

Is there any way to move the bones in script without moving the mesh with it? This way I can assign the mesh to be whatever values I want, and then just move the bones to match my new mesh and then hook up the bones so they drive the mesh again.

The meshes are all in SkinnedMeshRenderer's.

Thanks, Liron