sunk valves, stem height problem

I think you need to get the valves to the correct installed height and spring pressure you need for the cam you are running then if the tip of the valve is to high and the rocker arms don't touch the valve stem in the correct location you can shim the rocker shafts up to move the rocker arm to the center of the valve stem you shouldn't need to cut or grind .030 off the tip of the valve in order to make it work, but if the machine shop did there job you wouldn't be going through this stuff. It sounds like if someone opened a machine shop that did good work for a fair price they could make a very good living. Good Luck