I believe there is a provision for classic vehicles that you can use the same year plate as the vehicle, but I don't remember for sure. And as Steve stated, Broncos were not licensed as trucks, but it might be worth checking into anyway.
I thought the new plate law requires new plates every 5 years, where it used to be only when they updated the design. Now with so many different designs I think they had to pick a time frame instead. We just ran into that on my wife's car, which just turned 5 years old last spring. Permanent plates are exempt for some reason. I don't think plates go bad anyway unless they are damaged, but they needed to fund their new $20M facility somehow. %)
Sorry for the thread 'jack.