For some stupid reason , my 69 bee missing its bench seat , even though the ones i find cost a million dollars because everyone found out i need one, will a 68 work? Did yhey all have headrests in 69 ? Dont think the 68's had. Found a 68 seat local, and have a 69 4 door bench with headrests. Is it easy to install the headrests ? Will the 68 seat have anything mechanically different or cosmetically different after i reupholster it ? Thanks