Anyone use these for over 500 lift cam

You also order it based on the valve length as well. It's a trig program. He asks for the measurement off a t square from the top of the rocker shaft to the space between the square and the valve tip with the other side of the square parallel to the valve stem. With that measurement, he comes up with the type shim you need. He got my slant head dead nuts on. The rocker is in the perfect place on the valve tip.