What GARP said ^^^^.
On my 2005 R1200GS after disconnecting the beak from the side panels I removed the 4 tank mount bolts and pulled the tank back as far as it would go. Then I used a 15 mm "crow's foot" wrench head to remove the top bolt. The rest was easy, so to speak
. Thanks JVB: http://www.jimvonbaden.com/Ohlins_Shock_Install.html