you have to destroy a star nut to get it out [done that],
or push it all the way thru the steerer tube and out the bottom

the actual force the headset adjustment bolt applies is not really needing to be much.

after all the adjustment is maintained by clamping the stem around the steerer.
not the top cap bolt.

plus you don't have concern about scratch induced stress risers
developing into cracks, in aluminum tubes.

Expansion is step1, then I'd grease the center bolt.

I had a tourist's bike sent ahead, to put together,
the previous mechanic put the expander together, in a carbon steerer fork, dry,
so taking the cap bolt out unscrewed the expander , then I had to get the rest of it out ,
then put it back together, the better way.

Turned a 5 minute job into a 20 minute one.