Came across a real oddity at a garage sale last week: An official RCA Stereo 8 track "Installation and Service Test Cartridge". This is an alignment tool "checking head height adjustment, wow and flutter, frequency response, speaker phasing, crosstalk and track switching. Has a brief music section for each program, but since, as I understand it, the tape channel spacing for stereo and quad are the same, could a stereo tape like this be used to also check certain quad parameters?