The 3-spoke wheel was stock in `84 here in the US (last year for it), but the 4-spoke may have been available on an `84 ROW car.
So:
If you have the older-style SC seats, you need the 3-spoke.
If you have the later-style Carrera seats, you need the 4-spoke.
Post a pic of your interior if you're not sure about the seats.
