Before xmas I fitted a new mechanism to a rear door.the door itself was bowed which meant the door was a little bit stiff to lock I managed to get  all the hooks and rollers to engage in to the keep but informed the customer I would like to keep an eye on it. I returned this week to check it and it had improved I also replaced the handles which has made a big difference to locking and unlocking the door . I will return to see how it going in a months time