Removal of anti theft ignition switch

[Richard Guerra <rcguerra@domain.elided>]

Hello,
I am working on an Iso Rivolta (formerly owned by Richard Pryor) with an
anti theft ignition switch. It is the Sipea ignition switch. I need to
replace it. There is a bulge in the side of the casting that the switch
resides. There are two holes in the bulge. 
What is the process to remove it. I have the original ignition key, but
what next????

Thanks, for all input.
Richard Guerra
Sorry it is not an Alfa topic, but an Alfa person may need to know.

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