Tire Change
Changing tires on the GS is even esear then on the LT
First think, secure the center stand. It could move if you push hard.
Torx 45 to losse the break pads 
There is no need to protect the rim (like on the LT). The calliper will losse pretty easy.
Remmber not to push the breaks now. :) 
I use the BMW tool kit to do the whole service, just to make sure I can do it on the road, but is easy if you have a bigger tool. 
You have to remove the calliper from the rear wheel too. 
Then loose the main screw and the two lower fork screws. 
Note the position of the speedometer. 
Remove the center pin with a screw drive. 
Remove the spedometer 
"Park" your front forks the way ti wont' tip over, but that the rear whell has some balance. 
Tip the back towards the front and support the rear wheel off the ground. 
The front will be then firmely support.
Make sure you get the spacer. Don't forgot to put back latter. 
More GS add ons