Like I said Jason, Gobbs of talent !
As far as the copyright goes, If you create it and copyright it then I have to have permission to use it. Now if I was on the street doing an oil painting of a famous sculpture and then sold the painting I'm OK.
But if I drew the sculpure in its true likeness and put it on a Tee shirt without permission I'm open for a law suit.
An automobile is different. You can photogragh it, draw it or paint it but you can't build one that looks like it. Then you
are directly effecting their business.
If you build a one off car and copyright its shape then permission must be gotten before anyone can use its likeness. Many of the one off street rods are copyrighted. When they are photographed for the purpose of print the photogragher must have permission to do so. If you come along and take a picture, as thousands do when these cars are shown, Then there is no foul unless you use it for monitary gain.
So if you draw a reasonable facsimile of a GT, you can copyright that image. Nobody
can then use that image without your permission unless you sell the rights to that image. You are not copyrighting the GT40. You are copyrighting an artistic representation of the car in your art.
Common sense goes a long way here. Just don't pledgerize or copy somebody elses work.
When you make an original you should always mark it with the copyright symbol and the date it was created. I always enclosed a copy and a photo of the work with original thumbnail sketches in an envelope and mail it to myself to get the post mark. I file the envelope away unopened. If there is ever a dispute as to the creation of the work you can prove when you created it.
I hope this helps.
Hersh