So how about using this, http://www.thingiverse.com/thing:624625.
First off is that too much too complicated? If so we can just make some sort of plate you can screw mount things too instead of clamping.
Then rig up the gregs wade gears to run it, or I guess to make it really simple custom gears so the steps per mm would not need to be changed in the firmware. Then CAD up a stand to hold the stepper, gears, chuck/plate, done! Then just plug and play. as for the other end it can either be another chuck/plate or 2 bearings v holder to hold the stock since force will only be applied mostly in 1 direction.
hmm dang it I want to prototype but I have to pack boxes.