I recently modified a used/cheap boat trailer and made it into a steel flatbed utility trailer to haul my ATV around. I mounted the license plate onto the back of the right rear fender in existing holes where it was obvious a license plate had been mounted before. There was even a hole drilled on that side for the wire to come through for the light. My dad, a retired Texas law enforcement officer, says that I mounted it on the wrong side of the trailer. He is the type that is quick to point out anything that I have done wrong, which is probably a good thing. The light kit that I bought for the trailer has a clear lens at the bottom of the left taillight (for a license plate light), and the right side does not. I googled for a while and could not find any law/regulation that says the license plate must be on the left side of the trailer. Someone on this site must have some expertise in this area. Could it be that different States have different regulations regarding this topic, and this trailer could have come from some other State? Or, did I screw up yet again?