Exhaust was getting into the cockpit. So I had some leftover exhaust pipe, and extended them past the rear valence. But the hole in the tunnel I had to cut to get the tremec to fit is the new problem. I thought I could ignore it, but hot air, fumes, and noise come in, making driving any distance uncomfortable.
I have zero sheetmetal skilz, though, and this is a compound curve. Fortunately, my inevitable hack job will eventually get covered by the carpet. I plan to use sheet metal screws to hold it in place, as I have zero welding skilz.