Well after the advice i got on here, i got the soldering iron out whilst dodging the s***e weather we're aving and heated the screws up , whilst getting the oval plate out of the way first as it was a pain to get the maul grips on , and after a few attempts BINGO !! got them to undo, and the one screw with half a head on , came out easy enough as there was enough of it left to get the maulers on . and fitted the new ones in 5mins , alot easier with the allen type screw to put on
Thanks guys for the info !
(didn't think there would be a search on these on how to get out, cos it looks so easy , but nothing easy for me , sure i got a big S**t cloud over me when i do a bit of diy )