1970 Duster bench seat headrests removal

I read everything from tugging extremely hard from the lowest headrest position too sliding a thin piece of metal behind the headrest poles to release what ever it is that is holding them in. I have tried both to no avail :banghead:and don't feel comfortable trying to force them off. Mine are nice originals, albeit they need to be dyed and a new chrome strip installed....I don't want to damage or crack the vinyl.
(Plan A) I'm gonna take the seat to the upholsters shop,for new skins, and I will have him remove the headrests..
I may try, one more time, to pull them out once the seat is removed from the car since there will be more room/leverage but if they don't budge refer to plan A.