Here are pictures and other info that I have learned about the BTC mill.

This is the picture of the entire machine its big and heavy. It is about 10 feet tall and ~7,200lb.
http://img116.imageshack.us/img116/1109/allmn1.jpg

For now I will stay with old steppers as I need to get it runing ASAP. The screws have ~.001 backlash. For the spindle motor I pulled out the old DC 7.5hp motor and replaced it with a Baldor 6hp AC motor and VFD.

http://img338.imageshack.us/img338/2...anfrontty2.jpg

I kept all the bolts and nuts organised in ZipLoc bags, it took one day to put it all back together!
http://img338.imageshack.us/img338/4213/bagsfv8.jpg

The screws look pretty good.
http://img338.imageshack.us/img338/5...llscrewfl0.jpg

More pics
http://img338.imageshack.us/img338/7112/cleanallau5.jpg
http://img338.imageshack.us/img338/5...eanheadut1.jpg
http://img64.imageshack.us/img64/2117/cleansidepw4.jpg
http://img338.imageshack.us/img338/7...anside2ay5.jpg
http://img64.imageshack.us/img64/9563/cleanxcu6.jpg
http://img103.imageshack.us/img103/6418/cleanx2iy2.jpg
http://img160.imageshack.us/img160/5...eecleanum5.jpg
http://img160.imageshack.us/img160/8...eclean2oi5.jpg

For some reason the quill got stuck and will not go up or down, so I unscrewed the Z ballscrew bracket and used a 4 ton ram to push the quill down untill it fell out of the head. The quill is nice and shinny and smooth and so is the housing. I think the old oil got gummy and was holding it tight. I applied new oil on the quill and it moved up and down like on ice.
http://img128.imageshack.us/img128/7176/quillkg0.jpg
http://img128.imageshack.us/img128/6...housinghe1.jpg


The spindle in this thing is almost 4 feet long and has all the spring drawbar components inside. It has a double drawbar, one that moves the stud gripper down and another to lock the gripper.
http://img128.imageshack.us/img128/2314/spindleva5.jpg




Here is a pic of the tool holder a 40MMT.
http://img106.imageshack.us/img106/3028/toolst2.jpg


Stepper motor.
http://img117.imageshack.us/img117/8703/stepperde7.jpg