That's pretty wild!
With the grille altered you could do a two tone paint like this: (can see it light and medium gold-brown)

 

I keep hitting the "Buy it Now" button and nothing happens.​​​​​​​.. help

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Rat Fink a.k.a Ed Roth ! He's was the man.

 

Truthfully Ed Roth's stuff never connected with me. I remember him mostly from the Revell Rat Fink models from the 60's and the first Hotwheels cars which had a few of his creations. I was always drawn towards slicker type stuff, my two current car heroes are Rick Dore (he was the car designer on the tv show Car Hoarders) and there's nobody I know of that is near as creative as Randy Grubb. He is unbelievable.
Here's randy's website, I love his aluminum rivet stuff: Randy Grubb, The Blastolene Indy Special, Jay Leno Tank Car, Decopods and Decoliner
Ultimately, I'd do my revised HHR as a car that would look like it was not a custom but a production car. Maybe it would sport Buick emblems and be a Buick HHR, in the same way that GM used to make Nova's as Buick Skylarks that were outfitted with nicer seats and more

options.
Here's one of Rick Dore's cars:

 

Young car designers where feed their ideas from the earlier masters. Car design is an art form.