CenterlineT,
This is possible but expensive and involved if you currently do not have detachable head rests. Take one to your local upholstery shop and ask them what would cost for the seats you want modified. If the holes are already on top, it should be a piece of cake. This guy sells the metal frame
https://www.ebay.com/itm/CESSNA-HEAD...-127632-2357-0
Last year during covid when i had time, i stitched up my own seats. Trust me, its A LOT of work to make changes or new. I couldve made the headrests separate but i decided to make them part of the seats.
https://ibb.co/wLfj2Mk