Most popular tach in the 70's and other stuff

Down here in da south we Ran Dixco Tachs and the housing was decorated with a Confederate Flag. From 1973-1975 I owned a franchise of Don Garlits speed shop in Temple Terrace Fl. I remember having Thrush poster on the wall that showed a single Thrush labeled " Mono" and below it two Thrush mufflers and labeled "Or Stereo"