Probably best to take off the sway bar and trans mount so you can get a good pair of hands on it. Obviously just support the transmission case with a jack or block of wood or whatever.
That rubber boot with the drip on it is indeed the reverse switch. It's got two tabs/ears on it that you pull on to pull the boot off the switch body. Take a close look at the wires and DON'T cut them. They are bullet terminals that press into the switch holes. Carefully pry them out of the switch with a flat blade screwdriver.
The switch itself is easy to replace because it has a hex body on it and it just screws into the trans. Like the guys said, make sure to retrieve the pin with a magnet tool. Once you get the switch out, you'll see the pin is a simple round length of metal with a reduced diameter end on it that engages the hole in the switch body.
http://forums.pelicanparts.com/porsche-911-technical-forum/422046-reverse-light-switch-woes.html
If you'd like, I can show you a picture of how the pin is activated inside the trans. It's crazy how it's a few pins that hit each other and push the contacts inside the switch.