Below is a Dean Heacock pic of a XXX hopper.
The kit as delivered isn't that close to the car you see above. You will need to paint the ends yellow again. The whole end needs to be yellow not just the sides. You will need to add the C&O end letters and numbers (seen just right of the brake wheel). You will need to add the offset edge (seen in yellow right above the brake wheel), this part does come included in the kit but make sure you add it. When you weather this kit make sure to weather the old C&O logo and numbers more than the XXX. The XXX and yellow ends did not originally come on the car and were added after the other markings had been on for decades.
This is an 80% accurate sort of kit, don't worry about it too much, just weather it heavily and keep it in the middle of the train. If I ever find a better XXX hopper I will do a review of it and tell everyone to stop buying this kit. But for now, buy it if you find it cheap, otherwise spend your money on the Stewart or Bowser hoppers if you are looking for accuracy.
Below is a pic of mine.