I've lived in a few states that required plates both front and back, but I just ran with a plate on the back and club plate on the front. I never got questioned about it. I did get pulled over once for "driving a collector vehicle after dark." I explained to the officer that I had regular registration, buying new tabs every year, and was not bound by the state's collector registration limitations. He was too head up to crack down on collector plate abuse to take the time to check first that I didn't have collector registration. I've also been pulled over for using hand signals and not having operating brake lights at the corners. I didn't get a ticket for any of these because I was right, would have gone to court to prove it, and officer would likely suffer career consequences for losing in court.