Isolating Input and output jacks?

[sirreg]

Sure this be done. Or sure you use the ground of the case?

[Mike Burgundy]

I usually use the input ground lug as the central ground point, and ground the output through the case (so no wire running to it)
If you're really, really particular, you should isolate the output jack and ground it directly from the input lug. Rather unnnecessary IMHO.
hih