Thanks for the input guys. The old slave cyl failed in the same way with the old master, then the new slave with old master, then second new slave with new master, so I don't really suspect the master cylinder at this point. I mostly suspect the adjustment at the pedal, but I was looking for someone to confirm that and hopefully give me some advice on the subject. Doing it by trial and error will be a literal pain in the backside!
The transmission internals seem pretty smooth and tight when the slave cyl was working and the clutch etc was replaced in Sept. 08 so it shouldn't be anything that major. It seems like I am just missing something small like a proper adjustment, but I can't really find any specific info anywhere. It's frustrating because there's really not much to changing the parts and everything looks pretty obvious when installing the new. I would have thought that the master cyl would mitigate most differences from the pedal and control the pressure that is sent to the slave cyl, but I'm obviously wrong on that account.
If anyone else has any wisdom on the subject I would certainly be glad to hear from you. I'll get it straightened out yet!