It looks like a camp tightening issue. I loosened the clamp connecting the cat pipe to the resonator, moved it back slightly and re-tightened the clamp. The leak stopped.

But the leak reappeared at one of the other clamps. So I loosened each up as it leaked, moved it back slightly and re-tightened.

Feels like a game of wack-a-mole.

The original leak has now been resolved. The one that seems to leak the most still is the clamp at the rear of the resonator.

So how tight is tight? Is there a danger of over tightening these clamps? Is the clamp location (approximately 1/2" from the end of the female end) too far back?

Is some small leak from one of these connections okay? That is, will it just go away by itself as some rust builds up at that point??

I'm learning :)