This isn't quite exact, but 1/4 cup of butter (so a half stick if you're in the US) is 57 grams according to the conversion chart from allrecipes below. So use just a slightly heavy 1/4 cup or 1/2 stick.
Yellowtail, including Yellowtail Jack (Seriol landei), are recognized by a yellow stripe across their body and their yellow tail. Range & Habitat: Yellowtail is caught year round, but more commonly during summer in the Pacific Coast and the Sea of Cortez. They are caught primarily with hook and line, and their average weight is 10 to 20 lbs.
Females are generally larger than  males. They can weigh an average of around 700 to 1100 kilograms  (1500 to 2400 pounds). Giant great whites of weights upto 2200  kilograms (5000 pounds) have been caught by fishermen.   Adults great whites are on an average between 4 to 5 meters (13 to  17 feet) in length.