Bozo Texino

In the days before spray paint, people used to tag railroad cars with chalk, or a grease pen maybe... Bozo Texino was seen on a lot of cars. Two guys went looking for the person who drew this graffiti. They found him. He had worked for the railroad. He used to inspect cars. He would tag a car after he had inspected it. There was an original Bozo Texino before this guy who went by Grandpa. The first Bozo Texino was also a railroad worker. His version was a bit more intricate and very interesting. His name was Mac McKinley and he worked in Laredo, likely inspecting cars?