I actually cut out a piece of chipboard with some blocks on which hold the
F1 pedal unit in place, the chipboard then fits under my desk and with its
edge up against the skirting board to prevent any moving about. I also don't
use the springs in my pedals any more after the original set broke. Whilst
waiting for my replacement springs I rigged up the pedals to use simple
bungy cord which attaches to small hooks on the chipboard (I have several
hooks at different distances to give greater or lesser resistance). I found
this so much better that even though my springs arrived very quickly I have
never gone back to using them in place of the good ol' bungy. It may seem
like a lot of trouble to go to but the pedals don't budge an inch whilst in
use now and the cords are easily replaced if required.
Peter Hooper