It's not really a half-day job... though it sure seems like it.
1. Remove front rack. Two 12mm bolts, two 10mm bolts, and two more 12mm bolts up front.
2. Remove the black hood. Two plastic "screw" snap things.
3. Remove the gas tank cover. Two more plastic "screw" snap things and two 10mm bolts.
4. Remove the gas tank. Two 12mm bolts at the front of it and two 10mm bolts at the rear. Also don't forget to turn the fuel valve to OFF and disconnect the line from the tank to the carb (using pliers).
5. Lift the gas tank off of the machine and set it aside.
6. Remove the white damper thing. I'm not sure how to get this off without breaking it, so you're on your own. Mine's been broken since the first time it came off, and doesn't appear to hurt anything.
Now you can get to the valves.