This is a very simple and straightforward task. :smile: There is one phillips screw about halfway down the driver's side of the handle. Remove that and pull straight up.
The top of the handle holds a spring which provides tension to the button. Be sure to put the spring back in when reinstalling. It isn't tricky to reinstall the shifter either; place the spring behind the shifter button, then slide the shifter handle down over the shifter shaft until the hole for the phillips screw lines up, and reinstall the screw.