yes, its possible
i did many meshes that way.
But you need to split up your meshgroups.
So you have one group for the body, one for the alpha and one for the shoes.
If you want to do it yourself and dont want to add extra groups to your outfit(as those need to be updated also) i suggest you start with the female nighty
That mesh has 3 groups that you can use.
My first alpha mesh with reflective shoes is here, if you want you can make a clone with bodyshop and attache your own mesh to it.
http://www.insimenator.org/showthread.php?t=45294