Recently replaced my suspension fork with a rigid one. Now the headset is loose. I transferred the crown race from the old fork to the new one.
The top nut was tightened down with the stem bolts loose. No dice.
Any ideas? Did I put the headset pieces back incorrectly?

Remove the top cap. Is your steerer lower than the top of your stem? By how much?

Did you really have to open a new thread when there was an ongoing discussion about your issue in your original thread?

Anywho, check online. The manufacturer of your headset should have a diagram of how the headset is put together correctly. Good luck.