I bottom-out the front end all the time (damn Georgetown potholes!)...  But, I've never bottomed-out the rear end.

You may just want to look into a better shock...   :dunno:

I hear you man, the Katana shock will be much firmer I'm sure.

But even still, there might be too much travel that my fabricated passenger brackets hit it anyway.  And if I can get by just bowing them out (that is if this 7-setting doesn't work) then I'll probably go that route.

But  

Here's a video I made on how to adjust the rear suspension
http://www.sharebigfile.com/file/13827/GS500F-AdjRearSusp-23Jul06.avi.html
I read a ton of posts after having my own trouble with the spanner tool.  The trick here is not to use the spanner tool and instead use a crowbar.  DO NOT USE A PHILLIPS HEAD SCREWDRIVER.

Spanner tool worked fine for me...  I'm downloading the file as we speak, but basically, you have to be on the chain side.  insert tool into holes (not that hole you butt-head) from the rear.  Then you pull the tool towards the front (again from the chain side).