Bad luck! I think you are right about just paying the non-moving violation.
I'm always worried about being in the same situation, but I'll be damned if I will drill the holes to mount the factory bracket. What a horse**** design for such a great car!
I carry the plate and the tow-hook bracket mount in the boot, and hope I can talk my way out of it by saying " I must have forgotten to put if back on after getting off the track. Track won't let you leave it on for safety reasons, etc." Hope I never have to try that lame approch.
This year at the Barn at GT Joey's, there were a father and son who had a retractable bracket that bolted on the splitter underneath.
It seemed to be a good application on the father's Ferrari, but I'm not so sure about the GT. The baracket - sans plate- that was mounted to the GT had some severe signs of rubbing on the pavement, and the plate wasn't mounted. Looks like you might do some serious damage to the plate if you went that way.
The company makes a fancy version that is electrically powered, and has a remote switch like a key fob. I guess the idea is, while the LEO is walking up to your window, you push the remote and then say, " of course there is a plate there officer"!
The GT guys were going to mount this unit on the GT, but when they went to test it first, it proved to be defective. It's cable-driven, and the cables were snarled and would not work properly. Don't know what that says about the engineering of the thing. I do know that it says the GT Guys know their stuff by testing first. Those guys are the GREATEST!
If anyone is interested, the company is Altec Products, at altecproducts.com - 800-797-9035. I went on their web site, but couldn't find out much about this unit. They had a picture, but no details and no price, so I passed.