Cutting an old shotgun the right way

The customer wanted to shorten the barrel on his old double barrel shotgun. He no longer bird hunts or shoots clay pigeon, so it was just under his bed for home defense. As we all know, 18 inches is the legal limit for a shotgun, so I measured twice and cut once. The overall length went from 26 inches to 18 1/2 inches, half an inch matters..... I feel like it turned out really nice and the customer likes it. Now he can go out and shoot two blasts into the woods to feel safe..... Biden promises this will work. Let me know what you think?