seams like this is a common problem, a mate and i had the same problem on his g60 Corrado, in the end we drilled out the holes and made them a tad larger so the locking nut key from my set of bolts fitted his set. It was quite easy to do. We did try the Socket thing (gator grip it was called) we got from homebase but it fell apart and was no use at all luckily homebase decided it was a fault with the product and offered a full refund good luck they didn't see the hammer marks on the bottom where we "gave it a little persuasion" with a claw hammer after it had started to fall apart!!!