The stock radios for 1974 were AM, AM-FM mono, AM-FM Stereo, AM w/ 8track & AM-FM 8 track. The radios looked very similar to the early (78-83 or so) 5th gen radios, but had different wiring plugs. They mounted to the dash with jam nuts on the radio control shafts. I don't know exactly what information you were seeking, but I hope I was of some help.
Bill