, couldn't get the rattle gun into the allen-head, because it was seated too deep into the lower leg, so only option was using a chunky allen key, with a piece of 1/2" waterpipe as an 'extension bar' - it took 2 of us to undo the bastard, one holding the home-made tool down the inside of the forkleg, and me heaving on the extension bar. Jobs like this, it pays off to have a steel workbench that is bolted to the floor 
Shit it was tight !! but it did come off, and the job could be completed.....
The lower fork-bolt needs to be Loctited into place as well.......
