The 1971 boat-tail Riviera (CC here) origin myth has it that it was based on a rendering by John Houlihan, scaled for the mid-sized A-Special body, like the Pontiac GP. That rendering is below, and it clearly shows a lot of resemblance to the final and larger E-Body Riviera. But then I ran across this Riviera concept at glen.h’s collection, and it’s quite different than Houlihan’s rendering. And it’s lacking the distinctive pointy boat-tail. But it does have the Sting Ray rear window, and the distinctive side sculpting.
Here’s the Houlihan sketch that supposedly launched the ’71 Riviera, to satisfy Bill Mitchell who wasn’t exactly content at not having a car in production without the signature Sting Ray fastback. Can’t have that…
There’s no question that Houlihan’s front end is very much what was adopted for the production Riviera.
This Advanced Design model is totally different in the front. Which raises the question: were there older ideas floating around for the ’71 Riviera? Or just alternatives? Another interesting point: this one is clearly labeled “E Body”. And it has Graham Bell’s name on it, who was Assistant Chief Designer, GM Design until 1974, when he moved to Ford. Let’s keep us guessing….