It's no secret. I got it from
http://24designs.net. Paid $18 for it.
They only have them listed for the Soltice, GTO and smaller Pontiacs, but they do custom work too, so I got the dimensions and sent them to him and he fixed me up. Here's how I did it. I downloaded a pic of the Solstice Autobot emblem he had on his website, then did a cheap and dirty edit to make it red. Finally, I took the dimensions of my original Pontiac emblem (just the part that's in the chrome frame) and added that to the image, then sent it back to him and he made it to those specs.
There's a couple caveats - his emblem is flat, it is not beveled in the middle like the original. I got around that by adding extra two-sided tape on each side to 'build it up' a little, leaving the high point in the middle of the frame without extra tape. It seems to have worked but as I told the guy, time will tell if it can stand up to car washes and cold weather.
One other thing, their stock black ones are apparently aluminum over plastic. When I asked for red he said it would be vinyl. Not sure why but It came out pretty nice. I did tell him that if I do it again I'll ask him to run the red out to the edge and skip the silver border. He seemed very open to ideas and we went back and forth a couple times about the bevel and he seemed eager to make me happy so he might figure a way to make the bevel if there's call for it. Let me know how you make out. I told him I'd be sending him some business.
Edit: He has Decepticon emblems too, as well as others.
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