Got my new slider handle, how do i swap the lock barrels?

[The_blue]

Can anyone remember how to get the lock barrel out? I've done it before to clean glue out the origional but can't see where its fixed on this one! Was sure its an allen key type rub screw Or was that the rear lock....

[Aidan]

there's a little grub screw approx in line with the rubber seal then once you've undone that and with a key in you can withdraw the lock and nb the spring at the end