You're refering to infinitiplate, and they are having issues right now so they're not an option. The only viable option we have these days are the Stillen product... however thats not an option for the OP because he has an altered front bumper.

 

Same thing here in IL people getting pulled over, i know i have, but they never pull over a damn camaro or corvette

 

Something that I did on my Honda Prelude when I had it was to buy those rubber suckers that attach radar detectors to your glass window. I used two of those to mount my license plate to the upper part of my windshield behind the rearview mirror.

Saves money from having to buy brackets and also there is no drilling involved!

I don't know if this will fly in another state, but it's always worked fine for me.