Hmmmm....I know they used Camaro tanks on these cars too. Most Contemporarys that came with fuel cells, were produced (I believe) by a company called Triangle somewhere in FL. It was a 20 gal cell.
The wind wing issue is not unique, many have the same issue, all depends on the setup, that is why I mounted my Raydyots on the windshield and did away with the wind wings, but I had a 289FIA.
I know most parts were supplied to Peter Bayer from Finish Line and Cobra Restorers, you may check with either on the seats and tonneau cover.