How do you remove a lock barrel?

[Morseman]

Done it!
If anyone else ever has to do this, when you get the 10mm nut off, the plastic top with the tab that goes into the metal flap to lock the top of the box, has to be levered out as it seems that the locktite used to secure the nut sticks the threaded part of the barrel into the plastic part. I used a flat bladed screwdriver and it takes a bit of force. Don't loose the ballbearing and watch out because it is spring loaded and can pop out at almost any time whilst the cap is off.
Be careful when you put it back together, the tab can be put in the wrong way round, so that the key is trapped when the box is open, and trapped when it is locked. Also, don't forget to put the metal locking tab, that stops the box being removed when it's locked, back on and the lock cover tether into the little tab as well...

[sledgegreen]

I am not sure about the Trekker model, but I think that when I changed the locks on my old style Givi panniers there was a nut on the back which held the lever on the barrel. Below that was a small circlip which held the barrel in place. Having removed nut, lever and circlip, I then had to insert the key so that the little wafers were withdrawn into the barrel, and then the barrel came out quite easily.
Is the circlip still in place?

[Morseman]

I did, eventually, manage to remove the barrel.

I changed it for the same one as for the two panniers and all was well. For a while...

Then the little nut on the back of the barrel became loose and fell off and the new barrel fell out!

I'm now going to put the original barrel back in and just accept that I will have to use two keys. this time I'm going to use threadlock and even shelack on the nut to stop it comming loose!