Reader Alex sent me this link. Jump to the 22:03 mark to see the AR18S.
You can definitely see the unique flash hider on this gun. If you need one for your shorty project head over to AR180Parts.com. I just got a batch back from John Thomas at Retro Arms Works and they are ready to ship.
Been some time and relying on memory re post many years ago on Sterling Web Pages re King Hussein using his AR-18S to successfully defend himself against a hostile palace coup. By all appearances and the date of the interview this was a Costa Mesa AR-18S. Thanks to Alex.