Are you running a stock headset?
If so just buy a new Threadless Sealed (best) or Unsealed headset. Keep the O ring inside the top cap. Install headset, put the new crown race on the fork after pulling old one off. If you tighten the SCS and still wobbles, either starnut is to close to top of fork or needs a spacer. To fix just put a 1/4th inch (tall) spacer on the fork under your SCS. Then that should do it. Or if forktube is to long, run a 1/2 inch fork spacer. Should be good.