75-79 are non ECM in light duty vehicles, they are in-cap coil style,
80-up heavy 3/4 tons and heavier had non ECM controlled HEI too, but if was under about 8200lbs GVW then it got ECM HEI for the EST/ESC ignition timing emissions system
you are thinking of the 75-79 250 engine HEi that has sep[arate coil
there are some 84 v-8s that have separate coil however, but are rare
some of the caprices i know,
i dont know what GM was trying to do in 84, soemthing stupid