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.
Machinery's Handbook lists the density of southern yellow pine at from 52~55 pounds per cubic foot green and 36~41 pounds per cubic foot air dried. You might have guessed that the weight of a chunk of wood will vary a bit depending on its moisture content. (Resin content will affect density as well.)