I'm looking to meet with a gunsmith (or whoever properly fits a shotgun). I would like to be properly measured, evaluated for the proper shim, and change my recoil pad on my Winchester SX3 (mainly used for hunting ducks/geese). I realize most people just adjust this stuff to whatever feels comfortable to them. I can do that, but I'd like to be a little more precise and have it done properly. I live on the Illinois/Missouri border near St. Louis, so I'm looking for recommendations in either of these states. I don't mind driving a few hours, if needed. Any recommendations?