I deal with Canton Automotive Machine in Canton. Roger Decker is tops with Ford products. 330-453-8383 He is off Rt 30 just west of Rt 77. He's there on Saturdays til noon-ish. We usually have a group that does lunch so if you can't make it during the week, weekends are good also. He has motor dyno facility.
I am planning to have the heads done on my 302. I live in Elyria also and have been asking around. I have had numerous people steer me toward Wallace & Dewitt Engines, Inc, 8260 Leavitt Rd (SR58 west side just a little north from SR 113W) Amherst Ph 986-6111. Was told they do excellent stock, racing, and honest work.