They have ball and cup with the roller rockers that are on there now.
Not sure how many threads have to check!!!
can i use milimeters to measure the .30' you say too adjust the rocker? as i dont have a machinist ruler.
What kind of pushrods do you have now? If they are ball and ball they could be the wrong length. When you have the rockers adjusted, how many threads are showing on the under side of the rocker? Should not be many. Maybe 3.