license plate

In Pennsylvania the law clearly states that the license plate (we only carry a rear plate) on any vehicle has to be clearly displayed and unobstructed. In my case when the TC is on, you cannot see or make out the truck plate unless you crawl under the end of the TC. In this case you better pull the plate from the truck and display it somewhere on the back of the rig so it can be seen. In most cases the convenient spot is on the TC since they have a mounting bracket. My guess is that most if not all state motor vehicle codes state that the vehicle's plate(s) have to be clearly displayed. If you are carrying a short TC and as long as the trucks plate can be seen from a reasonable distance behind the vehicle, you should be fine just leaving it on the truck. If you are hauling a longer TC and the trucks plate is hidden, you best get it mounted to an area of the rig where it can be seen.