Yep - I did mine the other day. Open the pannier or top box. You will see 3 screws at the top of the hinged lid along the entire length. Remove the screws, and carefully withdraw the locking mechanism which runs the width of the pannier. Pull off the yellow bit in the lock. Insert the original key, and use a thin screwdriver to push a retaining clip on the lock barrel into the lock barrel - the lock barrel shoudl now slide out.
If you havent got the original key, youre a bit stuffed. However your dealer will be able to order one if you know the reg or chassis number.