How do you replace the ignition and tumbler on a Mercedes 1990 190E the wheel is locked and the key wont turn at all?

YOU WILL REQUIRE A SPECIAL CORE DRILL, MADE EXCLUSIVELY FOR MERCEDES, THIS WILL STRIP THE OUTER RING OF THE HARDPLATE FRONT, ONCE THIS IS REMOVED THEN THE REST OF THE IGNITION CAN BE REMOVED THE SAME AS NORMAL, I.E. : INSERT WIRES INTO PROBE HOLES AND RELEASE. I HAVE A G REG 190E TO DO TOMORROW (SAT 7th JAN), THE TOOL COSTS OVER A