Milt I had the same problem on my 986S , previous owner lost the " special " key/socket . As mentioned by others take a 15/16 socket preferable a 12 point ( more teeth ) and lightly pound it on . Do the security bolt on each wheel FIRST then the others . You only have to break that initial surface tension then they will come right out . The best part of this project is the noise each security bolt makes as you hurl them across the garage into a metal garbage can
I bought 24 used wheel bolts , four to replace the four I tossed and twenty as spares . Eventually one set will be painted silver the other set black because I have two sets of wheels . No more security bolt B.S.
If a professional thief wants your wheels he'll get them . If he can't get the wheels off he'll just steal the car ! Good luck getting them off .