e30 ignition barrel

[mark_i]

how to disassemble the ignition barrel?

barrel comes out of the steering column with a pin in the slot in position 1 no problem.
Not obvious how barrel comes apart to the replace the worn tumblers.

TIA

[mark_i]

thanks.
in the past I've been able to rebuild door/boot and glove box locks which can be taken apart.
Seems like the ignition barrel has no obvious way to release the centre cylinder from the body...