I've done a couple things to remove my stuck Kayfun fr my GUS top cap.
One is I blue taped the edges then 1 layer of paper towel or tshirt and a large wrench. It's an ugly process but managed with only a nic on the Kayfun.
The other is my wife has a jar opener made out of a sticky firm rubber. It has a number of sizes all the way down to 22 mm diameter. That worked also.
Since then I have placed small squares of blue painters tape on the top cap. I mean 4 little squares that u can't see once the atty is screwed on. It NEVER gets stuck any more. I am unsure wether it will effect performance, I've not noticed. I think that little bit of spacing which is visually unnoticeable has helped in keeping it fr getting stuck.
Ken