Need the original key to pull the barrels out of the existing locks.
Then you sit down with the new key and a box of wafers and exchange them so that they all sit flush - then re-insert the barrel into the lock. The barrel design is the same as in the link above - only the housing is different.
Or just buy a new case barrel kit and accept that they won't be the same as the ignition.
Or do a chip-less copy of the current (ignition) key and use that for your cases.
He immediately paid me the one of the highest compliments an Advrider can receive: "You're nuts!" (Alcan Rider)