After rereading the inital post he's got a Jessel system, he has no option except to remove the rocker assy, since if the geomerty is set right he only has 1 full turn adjustment. 7/16"X20 pitch=.050 total adjustment. I believe Jessel is like T&D's and they recommend 1 turn from full backed up adjuster as to where the geomerty should be.
Zip.