Texture Painting and Uv: how to control Target image? I am working on 3 objects: eyes, face and chest armor.

I have them on different layers and each one has a separate material and UV map. I have texture painted the eyes/face and when I switch to the UV mapped chest area and try to texture paint, it automatically switches the UV map to the one I used for the face and has the face texture on the chest.

If I switch to the UV map view and try to change the texture image to the blank chest one, it doesn't actually change on the model. I've tried setting up the nodes in cycles to assign the UV / texture I want to paint to, but it still stays at the face texture on the chest. 

I'm sure I am missing a step / not setting it up right. What do I need to do?
Thanks.

Here are some images to help explain better:

This is the UV map and texture I want it to use:


And this is the UV map and texture it auto applies:
sharing some pictures and the .blend file could help a lot
(since i don't have enough rep to comment your question i said it here)

anyway i show you the steps hope it helps:

first you have to set up a few different uv maps:




one for the texture and a few more for sides, back, top, etc.

you can use ALT+B to cut the mesh so you only select the vertices that are visible from that angle

like this


then align the uv with pictures you want to copy from 



after that go to texture paint mode and create a texture for the face

(explained in the picture) 


hope it helps