Too late for suggestions, I just brought it into the Meineke shop and said, "FIX IT."
I'm replacing the catalytic converter with a larger capacity model, and having a brand new manifold put on.
EXPENSIVE, but worth it.
My daughters and I all had a headache after driving to and from church on Sunday, sniffing the fumes and listening to the 'putter-putter' of leaking exhaust.
My Mom said the car sounded quieter when I backed into her driveway. I told her that was because not all the exhaust was exiting the MagnaFlow!
So, check your old manifolds.
And I wish we had headers for these things.