Same time delay relay on my 88 shelby z w light package. I believe it goes up to 1994. Time delay relay only works ignition swith light. Not dome lamp. You likely have an issue with the headlight switch rheostat, or a door switch shunting to ground. If the door switces use 2 wires with flat spades its a light package setup. If its a single barrel connector switch, the car does not have a light package
