Except for the fact that Shelby owned the rights to the Cobra name and produced Shelby Cobras. Any trade dress action would not have been aimed at AC who was allowed to build AC Cobras under license and permission of SAI but would have been directed to stop third parties.
Yes, I am making assumptions since it never actually occurred but I believe my assumptions are valid. I do believe SAI would have been able to win against third parties.
Not saying I own a real Shelby Cobra or anything but just addressing the trade dress issue as opposed to the trade mark issue.