Jim Carter's
bushing and seal removal tool (50% of the $53 is returned as a gift certificate when you return tool).
As SWEET states above, this tool is only needed when you need to remove an old original bushing or a worn-out Okie bushing AND you are not taking the rear end apart.
If you are taking the rear end apart, you can push out the old bushing (original or Okie) from the inside of the disassembled torque-tube. I have done this twice with a 5'-6' length of metal plumbing pipe (I forget the diameter - 1.25" to 2"). You need the largest diameter pipe that will fit inside the torque-tube without scraping the wall - a diameter that is larger than the diameter of the driveshaft end. You simple place the plumbing pipe inside the torque tube and hammer the pipe against the inside surface of the bushing/seal.
Note: at the end of the earlier torque-tubes there is a "stay-pin" that holds/locks the original bushing in place. That pin has to be removed (maybe someone will post the years in which this pin was used)?
I found SWEET's photos to be quite helpful. 
