noob here. any more I can do to these motors to increase value? pics included

Here's some pictures of what I'm working on:

http://imgur.com/a/5qQp1

Is there an effective way of taking the copper out of the armature?
The two large motors still have the windings inside the case, any tricks to taking them out?
The one winding I did get out of the case was a smaller motor, and I cut the case in half (it was an aluminium case that I wanted separate), any way of getting the copper away from the metal ring it's in? (pic 1)
The fields from the motors are covered in some kind of plastic and I can't knock the steel out of the middle (pic 2), any tips for getting these apart?



Thank you for your help!