Blue Heeler male. Fixed 3 years old no cats in Willits, California For Sale

I have a 3 year old Blue heeler fixed male. He is a great dog, kind and smart, but he hates cats, and killed mine. He is a large male, with the blue tick markings. I have raised him from a puppy, but could not get him to get along with my cats. He would make a great work dog as he loves to heel. Must be a good home only. He is young in this picture, and weighs about 60 to 70 pounds. Please help. We are located in Willits California.