Sorry to jump in on this CP forum, but I asked this question in another thread about a problem that I might have with the opto's on my CP. I am getting left & right jab ramp errors # 36 & # 38 switch not made error. Someone told me to clean my opto's, but I can't believe the problem is with BOTH ramps and not just one. Is that opto board mounted in the head or under the play field. Thanks for any help on the CP thread.