I agree, check with the search function. I can tell you though in my own case when I did my rebuild, the original ball stud heads had developed a sharp feather edge on the balls. I thought it best to just go ahead and just switch them out for new ones while in there lest these old ball heads cause uneven wear on the new rocker arm mating surfaces. You may even find it difficult to adjust the valve clearances properly unless you do the change out.