How to replace ignition tumbler on 2000 ml320 mercedes benz?

I would assume that there is a hardened steel sleeve "VERY HARD" that surrounds the barrel the same as the W140 model. the repair shop will have trouble cutting this off , like the novices at diesel motors in perth western australia. and will probably want to charge you around $3,000 AUD to replace the key and barrel. which collapsed in my case. jamming the key in the ignition. not bad for a vehicle that had cost $219,000 AUD , and had covered 220,000 km, when there countless thousands of 40 year old toyotas and holdens running around with the original ignition barrels. anyway , digressing , the switch that sits behind the actual barrel lock will no doubt fail not long after u change the barrel also. because i would say that the junk they manufacture for these over rated piles of trash (still riding on the reputation of their 1970's products, is about the same quality level as cheap rubbish componentry used in the W140 . "google search for W140 wiring harness there s a blog with a list of owners in the US with failed wiring insulation causing the copper wires to short out and in many cases cause engine fires. manufactured by Bosch to MB specification to be biodegradable, what a totally brilliant place to start , crucial electronic components, with severely limited life from the start.! , the ignition switch doesn't need to be cut out of the steel dash frame like in earlier models, and is not particularly hard to remove however the stealer will still try to slug u around a grand and tell u its a HUGE job. a friend of mine had my ignition barrel and switch out in 20 minutes after the switch behind the barrel failed after the dealer installed a new key and barrel and charged me 6 hours or so at $120/ hour.