We did two separate cars with 2.5" exhaust all the way out the back. One has OE wheelwells, the other was mini-tubbed with 335's on the back. I have yet to build a 3" but I do think it is possible. The first and second gen have about the same amount of room for running exhaust. I know you can do 2.5" and probably 3" on the second gen as well.
Brian Hobaugh SCCA National Tour June 2014
First Hemi 'Cuda Convertible Ever Built
Short clips: Goodguys Pleasanton autocross and pit videos
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