Just got my Katana rear shock.  Used, but looks to be in good condition.  Needed to clean it a bit, but aside from a few small chips in the paint and a tiny bit of surface rust, the spring looks good.  Damping rod looking clean, and I can't detect any signs of oil leaks (not that I really know what to look for).  Think I got a good one?

What's the torque settings on the GS shock bolts...or is it just "until they're tight"?

The way to test it - ironically, fit it in the bike and run it down a nice bumpy road. Then look at the damping rod for oil. Heck clean off the rod first with dry cloth. Then  install, ride etc.
I however open em, open and close the shock to full compression and see if I get oil anywhere, and I do it before I buy. If it is doa, I dont even buy it.
Cool.
Buddha.

Got the Clymer handy.  Torque values are as follows:

Shock absorber fasteners, upper & lower:  29-44 ft-lbs

In case you need them:
Shock rod fasteners:  51-73 ft-lbs
Shock lever fasteners:  51-73 ft-lbs