[speed demon]

hi all.
i'm in the proccess of building my cobra and im at the stage of building up the engine , almost done but ive hit a snag with the throw out bearing . Im using a mcleod push on adjuster screw and the matching screw on bearing assembly.
My question to anyone that might know is what stops the bearing assembly from turning on the adjuster screw when the bearing comes in contact with the pressure plate fingers?
It seems to me that it needs a locking nut behind the bearing!
Any suggestions would be appreciated.