Now that is an interesting question! The service manual and parts catalog show it, but neither mention anything about it. I will speculate here, since I have never done this, but I think you will need to remove the leather from the handle, so you can get to the button. Since the button is spring loaded, you will most likely need to push it in, after you get the spring out of the handle. Again, I have never done this, so be sure it is speculation....
HTH,
LArryB