the gap is back and I can hear some creaking. It looks like it's coming from the headset. My LBS is booked until next Monday.

So I took it apart again and moved one of the spacer above the stem. The gap got smaller but it's still creaking.

How tight is the expansion plug inside the steering column suppose to be? It's not very tight, less than 5nm for sure. Could that cause the creaking and the gap to get larger over time?