How to remove the pulley wheel flat headed bolt (Indesit WD12)?

I am fitting a new spider assembly to my Indesit Washer/Dryer WD12 and all was going well until I tried to remove the flat headed bolt (Torx T40) which secures the belt pulley to the main shaft - it just will not move! Assuming it to be threaded, is it right hand or left hand thread? Any suggestions? Next move would appear to be to destroy the pulley wheel.........