It's at Import Paint & Body on the recommendation of some of the high end (Porsche, Lambo, Ferrari, and used exotic) dealerships.

I think I found my place, but in case not I'll keep them in mind. I asked a used exotic dealer, they referred me to a Porsche modification shop, and they referred me to a person who I haven't yet spoken to (I was told he was hard to get a hold of) who apparently makes the exhausts that Panoz puts on the Esperante.