Allen, it takes a special device called a "pole shoe vise" to get those screws that hold the field coils out of the case. It's like a huge C clamp that is bolted to the workbench top that holds a big screwdriver bit like a drag link socket tight into the screw. Then a LONG handle is used to turn the screws. They've probably got close to 100 ft/lbs of torque on them, so the likelihood of an amateur getting 'em out is slim, and getting one tight enough to hold properly on reassembly is just about impossible. If the field coils need changing, that's a job for a pro with the right tools!
Jerry
