Yhe 500 price is not right, just a reference. Several flathead engines. Some 21 stud and some 24. One 21 stud has a rebuild tag on it. One LB 21 stud. One 59a, one is a 24 stud from a sprint car racer of the 40s. Releived block with a 180 deg. Crank. Cell 2two4-402-142seven. seems hamb won't let me load pictures so text for pics. and info.