About half of the restored cars I see have the cowl seal on (what appears to be upside down)... Or at least formed incorrectly. It is possible I think to mount it incorrectly, but I think it takes some effort to form the seal correctly when you install a new one. I recall back in the seventies, I purchased a new seal from Chevy, then I used strips of masking tape to keep the seal 'turned' out' the right way, until I got the hood down on it and let it sit like that for a few days.. then it was OK and has been OK since..
Gary W / 09C 69Z28-RS, 72 B 720 cowl console rosewood tint
69 Corvette convertible, silver/black 350 hp,
60 Corvette white/red, 72 Corvette coupe, '70 Mach I
90 ZR1 red/red #246, 90 ZR1 white/gray #2466
72 El Camino, '55-'56-'57 Nomads, '55-'57 B/A Sedan