An interesting situation came up at the local airport coffee drinking competition.  Can an IA/A&P override a return to service sign-off by a Repair Station?  A repair station changes some component(s) of a certified airplane.  Using materials and methods available to them thru the FAA, AC43.13, and their approved operations manual, they deem the installation to be a minor modification.  There is no appreciative effect on W/B, Structural components, or performance.  The airplane enters an ann