I used sugru to fashion a foot for the horizontal support to the top right of the picture to sit in. The support kept slipping and causing the cystern to overflow. Once cured overnight, the sugru foot allowed me to shorten the support, making it stronger, and it also gripped the wall of the cystern, preventing slippage. Without this, I would have had to buy a whole new flushing mechanism, and would undoubted have got very wet fitting it ! With this simple repair, I didn't even have to turn the water off. Mark, Essex.